Manchester United have signed some great players, but they have missed out on some even greater ones, writes Sky Sports News' Kaveh Solhekol.
If they had bought every player on this list, they would probably have won the title and the Champions League every year, and that's not an over exaggeration.
These are the 50 best players that got away - and a few they probably didn't even want...
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50. Nicolas Gaitan
Put 'Nicolas Gaitan' and 'Manchester United' into Google and you get 93,400 results. There are football reporters in the North West who, to this day, break out in a cold sweat when the Argentine winger's name is mentioned.
Gaitan was linked to United for years and years. The closest he came to moving to Old Trafford was in 2012 and a mooted £20m deal.
Work permit problems meant the deal was never completed and he stayed at Benfica before joining Atletico Madrid four years later.
49. Leighton Baines
David Moyes knew he needed to make signings when he became Manchester United manager in 2013. United had just won the title in Sir Alex Ferguson's final season and Moyes wanted to strengthen from a position of strength.
Cesc Fabregas and Thiago Alcantara were on his shopping list and so were two players Moyes knew well from his time at Everton - Marouane Fellaini and Leighton Baines.
Joint bids went in, including one for £28m. When Everton rejected them United started making separate offers.
Fellaini eventually moved late on deadline day for £27m but Everton held firm over Baines and the player didn't agitate for a move.
"I sat on the fence and saw how the thing played out," Baines later said. "Maybe it was just how I was brought up."
48. Alphonso Davies
Alphonso Davies is only 19 but he looked like the best left-back in the world in Bayern Munich's thrashing of Chelsea in the Champions League in February.
Davies had been watched closely by United and they even invited him to their training ground for a three-week trial back in January 2018.
But having just returned from a training camp with the Canadian Olympic team, his club at the time, Vancouver Whitecaps, refused to release him again.
Six months later they sold him to Bayern Munich for £14m, a deal that already looks to be worth every penny.
47. David Hirst
In September 1992, United needed to sign a strike partner for Mark Hughes after Dion Dublin broke his leg just six appearances into his career at Old Trafford.
Ferguson had tried to sign David Hirst before and now he decided to try again. United put in a £3.5m offer but Sheffield Wednesday refused to let him go.
United signed Eric Cantona instead and the rest, as they say, is history as they went on to win their first title in 26 years at the end of the inaugural Premier League season.
46. Erling Braut Haaland
There's no doubt Erling Haaland would have been a great signing for United, but it didn't happen.
The 19-year-old traded Red Bull Salzburg for Borussia Dortmund in January and United's inability to get the deal over the line will come as no surprise when you consider that Haaland's agent is a certain Mino Raiola.
45. Cyrille Regis
Cyrille Regis is famous for scoring breath-taking goals in West Brom's iconic navy and white striped kit. He would also have worn United's famous red shirt if Ron Atkinson had got his way.
Atkinson had worked with Regis at West Brom and wanted to sign him again when he was United manager in 1986.
A deal had been agreed in principle with Coventry, but it fell through when Regis was sidelined with a thigh injury.
44. Thiago Alcantara
Will he sign, won't he sign? Will he sign, won't he sign? Will he sign, won't he sign? Will he sign, won't he sign? Will he sign, won't he sign? Will he sign, won't he sign? Will he sign, won't he sign? Will he sign, won't he sign? He didn't sign. Next.
43. Ivan Perisic
His name is enough to send shivers down the spines of United fans. In the summer of 2017, Jose Mourinho decided he wanted to sign the Croatian winger from Inter Milan. The saga dragged on all summer.
The sticking point was Inter's valuation. They wanted €50m and United wouldn't pay more than €40m. On and on it went until the window closed, and Perisic stayed at Inter.
Perisic later claimed he turned United down because Inter's new manager at the time Luciano Spalletti asked him to stay. "That was very encouraging," Perisic admitted. "In football, small details in these situations are key."
42. John Obi Mikel
Manchester United actually signed John Obi Mikel from Lyn Oslo in 2005. The Nigerian midfielder appeared at a press conference to announce the move and was even seen wearing a Manchester United shirt.
But there was just one problem - Chelsea believed they had an exclusive agreement to sign him and they weren't prepared to let him go to Old Trafford.
After almost a year of legal wrangles, Mikel signed for Chelsea, but only after they had paid United £12m compensation.
41. Kerry Dixon
United needed a striker in the summer of 1986 after being forced to sell Mark Hughes to Barcelona. Ron Atkinson wanted Kerry Dixon from Chelsea, but pursuing the deal was anything but easy.
Dixon had scored 93 times in three seasons at Stamford Bridge and Chelsea wanted more than £2m to let him go.
That would have made him the most expensive player in Britain and Atkinson was not impressed with Chelsea chairman Ken Bates, who he accused of putting "a wildly over-the-top valuation" on Dixon.
Dixon stayed at Chelsea for another six seasons, scoring 100 more goals and cementing his place as a club legend.
40. Paulo Dybala
Swap deals are never straightforward. In fact, they are notoriously difficult to pull off.
Juventus wanted to sign Romelu Lukaku last summer and United were happy to let him go, but Juventus wanted Paulo Dybala to move in the opposite direction as part of the deal.
United were willing to take Dybala, after all, they needed a creative force and the Argentine was of the required standard, but there was just one problem - Dybala didn't want to move.
Then there were all the complications with third-party ownership rules and image rights payments to take into consideration, all of which resulted in Dybala staying in Turin.
Lukaku moved to Inter Milan and, six months later, United signed Bruno Fernandes.
39. Aaron Ramsey
In June 2008, Aaron Ramsey was 17. He'd just bought himself a lime green Ford Fiesta and he had the world at his feet. He was the most sought-after young player in the country. He'd played 22 times for Cardiff and they were ready to sell for £5m.
Manchester United, Arsenal and Everton all wanted him but United were favourites, and the signing was supposed to help their bid to become the first club to retain the Champions League.
Ramsey spoke to Ferguson, but he chose Arsenal after they pulled out all the stops, flying him on a private jet to Switzerland to meet Arsene Wenger. Ramsey later said he turned down United because Arsenal produce more young players.
"What world is he in?" Ferguson responded. "It was his own decision to reject United and I have no problem with that. He would have faced more competition at our place to make the first team."
38. Les Ferdinand
United wanted to sign a new striker in December 1994 and the player Ferguson turned to was Les Ferdinand. He had made a name for himself with his scoring record at Queens Park Rangers and they were ready to let him go for the right price.
Ferguson called Ray Wilkins, who had played with Ferdinand at QPR, to ask for a character reference. Wilkins had only good things to say, so United went ahead and made a bid. At the same time, Wilkins called Ferdinand and told him what had happened and said a bid was imminent.
Ferdinand went to see the QPR chairman Richard Thompson the next day and he was told he would be allowed to leave if he wanted. "It's Manchester United," Ferdinand said, believing a deal was now close. But that's when everything started to go wrong.
QPR manager Gerry Francis resigned when he found out Ferdinand was about to be sold. Thompson couldn't lose his manager and his star striker in the same week so he convinced Ferdinand to stay.
A few days later, Ferdinand was surprised to discover Wilkins was his new QPR manager. Wilkins had accepted Thompson's job offer on one condition - that Ferdinand was not sold.
"You've learned an important lesson," Wilkins told Ferdinand. "In this game you have to look after number one."
37. Matthijs De Ligt
Matthijs De Ligt would have been a great United signing last summer. The 20-year-old centre back had just helped Ajax reach the semi-finals of the Champions League. But his agent is Mino Raiola so it was never going to happen, and he ended up at Juventus instead.
36. Neville Southall
Neville Southall was one of the best goalkeepers of the modern era. He won two league titles with Everton in 1985 and 1987. English clubs were banned from Europe at the time otherwise Everton and Southall would have had a very good chance of winning the European Cup as well.
He spent 17 seasons at Goodison Park. Legend has it that it would have been only 10 if a proposed move to United had not fallen through in the summer of 1991, when United identified the Welshman as one of their top targets.
Talks were held but when no deal materialised. United turned their attention to Denmark and clinched what Ferguson described as the deal of the century by paying Brondby £500,000 for Peter Schmeichel.
35. Raphael Varane
Raphael Varane is one of the best defenders in the world so it's no surprise that he is continually linked with a move to United.
You know it's summer when stories start appearing about United and Varane. The only problem is that he plays for Real Madrid, so it is safe to say there is absolutely no chance of him ever signing for United.
Cynics would say his earning power is boosted every time a story appears claiming United are interested in signing him.
34. Peter Beardsley
People sometimes forgot just how brilliant Peter Beardsley was. He scored goals, he set them up - he was the perfect strike partner. He proved it every time he played for Liverpool and every time he played for England.
United bought him from Vancouver Whitecaps in 1982 for £250,000 but let him return to Canada after just one game. A year later they turned down the opportunity to re-sign him for £500,000.
Beardsley moved to Newcastle instead and in 1987, after scoring 61 goals in four seasons at St James' Park and impressing for England, he earned a £1.9m move to Liverpool.
United, now managed by Ferguson, tried to sign Beardsley as well but their offer was rejected.
33. Michael Ballack
No one was surprised that Michael Ballack turned out to be one of the best free transfers of all time after he moved to Chelsea from Bayern Munich in 2006.
He was a world-class midfielder and clubs, including United, Inter and AC Milan, had wanted to sign him as well.
Ballack says he chose Chelsea because that's where he thought he had the best chance of winning the Champions League. He may have thought United were on the slide but they won three titles in a row after the German midfielder snubbed them.
And Ballack's Champions League prophecy backfired in 2008 when United beat Chelsea on penalties to win the European Cup for the third time.
32. Jordan Henderson
Jordan Henderson is the player who makes Liverpool tick. Since his move to Anfield from Sunderland in 2011, he has developed into one of the most-effective midfielders in world football.
It could all have been very different though. Steve Bruce, manager of Sunderland at the time, recommended Henderson to his former club, but not everyone at Old Trafford was convinced.
United watched him closely and reports were written up. Eventually, they decided against a move because of his running style.
"We noticed he runs from his knees with a straight back," Ferguson said. "The modern footballer runs from his hips and we thought this gait might cause him problems later in his career."
Eight years later, Henderson lifted the European Cup as Liverpool captain and he has been the driving force behind the Reds as they stormed into a 25-point lead at the top of the Premier League this season.
31. Pedro
No one currently playing in English football has won more trophies than Pedro. At the last count he had 25 major honours to his name. No wonder United tried to sign him from Barcelona in the summer of 2015.
How hard they tried is debatable though. In the middle of August of that year, Chelsea announced they had signed Pedro from Barcelona for £21m. Louis van Gaal denied at press conferences that United had missed out on him.
Meanwhile Jose Mourinho, who was managing Chelsea at the time, said he had taken advantage of an opportunity. "United wanted Pedro," he said. "Then they didn't want him."
30. Paolo Di Canio
Paolo Di Canio and United would have been a match made in heaven. The enigmatic Italian could have had the same impact as Eric Cantona at Old Trafford had United succeeded in their attempt to sign him in January 2002.
According to Ferguson, the deal collapsed when Di Canio asked for too much money. "I tried so hard to get Di Canio," he said. "The deal was all done. We had made an offer he had accepted, but then he came back saying he wanted more. We couldn't agree to the new demand."
Di Canio says it didn't happen because he couldn't bear to turn his back on West Ham. Another theory as to why the deal fell through is because United needed to sell Dwight Yorke first and he refused to join Middlesbrough.
29. Michael Essien
You can't really blame United for failing to sign Michael Essien. They invited him to Carrington for a trial when he was just 17 but they couldn't sign him because of work permit problems.
Essien had been so overawed by the experience he was too scared to speak to any United players during his seven days in Manchester. He may have been shy, but he was still determined to make it to the top.
He took a roundabout route back to the Premier League via Bastia and Lyon before signing for Chelsea for £24m in 2005. At Stamford Bridge he established himself as one of the best midfielders in the world and won seven major trophies in eight seasons.
28. Toni Kroos
Toni Kroos came close to joining United in 2014, very close.
Kroos says he had a verbal agreement to join United from Bayern Munich, but the proposed move fell through after David Moyes was sacked.
Four days after winning the World Cup with Germany in Brazil, Kroos joined Real Madrid where he has won the Champions League three times, though that has still not stopped him being linked with a move to United every summer.
27. Terry Butcher
If United had signed Terry Butcher in the summer of 1986, Alex Ferguson may never have become United manager a few months later.
Ron Atkinson wanted to sign Butcher and the England defender wanted to move to Old Trafford after Ipswich had been relegated.
Atkinson thought Butcher would be the perfect centre-back partner for Paul McGrath. He raised the issue at a board meeting and he was stunned at the response when he asked for £750,000 to sign Butcher.
According to Atkinson, he was told Butcher was a good player, but the money had been allocated for the Manchester United museum.
26. Cesc Fabregas
United tried to sign Cesc Fabregas twice. The first time was in 2003 when he was at Barcelona's La Masia academy, but, having listened to what United had to say, he joined Arsenal instead.
The second time was in 2013 when David Moyes wanted to make him one of his first United signings at Old Trafford. Barcelona rejected United's first offer of £25m and an improved bid was also turned down.
Fabregas wanted to return to Arsenal and when they failed to take up their option to re-sign him, he chose to join Chelsea.
25. Trevor Francis
Ron Atkinson was a big fan of Trevor Francis. He tried to sign him when he was in charge of West Brom and he tried again when he became United manager in 1981.
In his autobiography The Manager, Atkinson says the United board vetoed the move because they were worried about the player's injury record.
"When I mentioned this to Trevor one night in Manchester, he became very offended and didn't talk to me for a couple of years," Atkinson said.
24. Manuel Neuer
Alex Ferguson's autobiographies can be a difficult read at times because he gives so little away. There are occasional glimpses into what was going on behind the scenes though, and in My Autobiography he devotes one whole sentence to Manuel Neuer.
It was 2011 and Edwin van der Sar was due to leave in the summer. Neuer, in net for Schalke at the time, had established himself as the best young goalkeeper in the world. Ferguson was a big fan and revealed in his book that Neuer was "on our agenda".
United's goalkeeping coach Eric Steele had other ideas though. He convinced Ferguson that David de Gea was the better prospect and United opted for the £19m Spaniard from Atletico Madrid instead. Neuer, meanwhile, signed for Bayern Munich that same summer.
23. Stuart Pearce
Stuart Pearce playing for United? It could have happened. The power, the tackles, the ferocious free kicks - Pearce could have been an Old Trafford hero with a drawer full of medals.
Alex Ferguson tried to sign Pearce twice, but Nottingham Forest refused to do business on both occasions. According to Ferguson, he even drove to Nottingham once to speak to Brian Clough about Pearce but the Forest manager pretended he was not at work even though his car was parked outside.
Ferguson was convinced Pearce would have thrived at United, stating: "This club is built for heroes like him."
22. Raheem Sterling
Virtually every big club in England was trying to sign Raheem Sterling in 2010 and United were no different.
Sterling, aged 15 at the time, was hot property. He had not played for Queens Park Rangers yet but the buzz around him was so big they were willing to cash in.
Sterling had cost them just £50 - that's how much they paid the scout who found him and brought him to QPR.
United sent their youth academy director Brian McClair to watch Sterling in an U18 game but Liverpool moved first and signed him for £450,000, rising to £2m.
Thanks to a sell-on clause, QPR eventually ended up making £11m from a player who never played for them and cost just £50.
21. Arjen Robben
Close your eyes and you can imagine Arjen Robben in a United shirt, beating a couple of men, cutting in from the right, not passing and missing the target from 25 yards!
If things had worked out differently the Dutchman could have been doing that every weekend for United instead of Chelsea, Real Madrid and Bayern Munich.
Robben says United wanted to sign him in 2004 and he blames them for the deal not happening. He met Ferguson and was given a tour of United's training ground, but he heard nothing back after he returned to PSV Eindhoven.
Chelsea were also in talks to sign him and he says he moved there because he liked their plans and there was no offer from United.
That sounds more plausible than Rio Ferdinand's recent bizarre claim that Robben turned down United because he didn't like the smell of their training ground.
20. John Terry
John Terry's slip during the penalty shootout in the 2008 Champions League final famously helped Manchester United win their third European Cup, but in a parallel universe the Chelsea legend could have been playing for the Red Devils in Moscow that night.
Terry grew up supporting United and he was invited to their training ground before he signed his first professional contract at Chelsea in 1998. Looking back, though, he cannot have any regrets.
He went on to play for Chelsea 717 times and won five Premier League titles, five FA Cups, three League Cups, the Champions League and the Europa League.
19. Gareth Bale
United knew all about Gareth Bale when he was growing up. They tried to sign him in 2007 and there was talk of a £10m offer when he was coming through the ranks at Southampton, but Bale ended up moving to Tottenham.
He claims to have chosen Spurs because he thought he would play more regularly at White Hart Lane, but Ferguson blamed Southampton for his failure to sign a player who would go on to win the Champions League four times at Real Madrid.
"It was not the boy who turned us down," Ferguson said. "It was Southampton."
Bale has continued to be linked with United in virtually every transfer window during the past five seasons.
Zinedine Zidane told him he could leave last summer, and he was close to moving to China. His agent though has always said Bale is happy in Madrid. Of course he is, the golf courses are amazing!
18. Wesley Sneijder
United's never-ending pursuit of Wesley Sneijder was the War and Peace equivalent of transfer sagas. It went on and on and on and it only really completely finally ended when Sneijder retired last summer.
No one alive wants to read anything more about United trying to sign Sneijder, so let's keep this brief - he was a very good midfielder and United tried to sign him a couple of times but it never happened. Done.
17. Sergio Ramos
Sergio Ramos has been at Real Madrid for 15 years.
Every time he has been in talks about extending his contract at the Bernabeu something strange happens. Stories start appearing in the Spanish media about United wanting to sign him.
These stories build up to a frenzy until a press conference is called where a beaming Ramos announces he has signed a new, more lucrative Madrid contract.
In case you're wondering - his contract runs out next summer. So, mark your cards, you've been warned.
16. John Barnes
'Catch me if you can. Cause I'm a United man. And what you're looking at is the masterplan.'
Don't laugh, John Barnes could have been a United player. United were interested in signing him before he moved to Liverpool in 1987 and Ferguson has admitted he made a mistake by not trying to do a deal.
United's scouts were not convinced that Barnes was right for United and, in any case, their Danish winger Jesper Olsen had just signed a new long-term deal.
Ferguson regretted not signing Barnes but the player never looked back. In his first season at Liverpool he won the title and was named PFA Player of the Year.
15. Petr Cech
In 2003 Ferguson went on a scouting mission to watch a young Czech goalkeeper playing for Rennes. He had received glowing reports and it was now time for a personal check on Petr Cech.
Ferguson was impressed but not convinced that Cech was what United were looking for at the time. "He was 18 or 19," Ferguson remarked. "I told myself he was too young for us."
It was not a wasted trip as far as Ferguson was concerned though. Another player caught his eye and United ended up paying Nantes £3.5m for Eric Djemba-Djemba.
Meanwhile, Cech moved to Chelsea the following summer and stayed there for 11 seasons, winning four titles, four FA Cups, three League Cups, the Europa League and the Champions League.
14. Patrick Kluivert
After relinquishing the Premier League to Arsenal in the summer of 1998, United needed someone who could guarantee goals and only the best would do.
A £9m fee was agreed with AC Milan for Patrick Kluivert but the Dutch striker refused to even talk to United. He said there was only one English team he'd be interested in signing for and that was Arsenal, before eventually joining Barcelona.
"Maybe he doesn't know how big a club Manchester United is," Ferguson said before bringing in Dwight Yorke from Aston Villa for £12m instead.
In his first season at Old Trafford, Yorke scored 29 times and United won the treble.
13. Gary Lineker
United had two chances to sign Gary Lineker in the late '80s and failed to take either of them. The first time was in 1988 when Barcelona made the England striker available for £2.5m.
United had just bought Mark Hughes back from Barcelona for £1.8m so spending that kind of money, in those days, on another forward was out of the question.
Lineker stayed at the Nou Camp for another season before Tottenham brought him back to English football for £1.1m in the summer of 1989.
According to Lineker, United were approached when it looked like Spurs were struggling to complete the deal but he eventually moved to White Hart Lane on June 14.
He has since hinted he chose to move to Spurs instead of United. "You have to remember the Manchester United of 1989 weren't the Manchester United of four or five years later," he said.
12. Antoine Griezmann
United were prepared to trigger the £87m release clause in Antoine Griezmann's Atletico Madrid contract in the summer of 2017, but the Frenchman decided to remain in the Spanish capital.
With Atletico banned from signing players by FIFA and unable to sign a replacement, Griezmann stayed and signed a new contract saying it would not be right to leave under such circumstances.
He did leave two years later, and his departure was anything but harmonious. Barcelona waited until the summer of 2019 when his release clause dropped from €200m to €120m before they announced he was joining them.
Atletico wanted the full amount because they said a deal between Griezmann and Barcelona had been agreed months earlier. The dispute was finally settled with a private out-of-court settlement last summer.
11. Virgil van Dijk
Jose Mourinho wanted to sign a centre-back in the summer of 2017. He had Chris Smalling, Phil Jones, Marcos Rojo, Eric Bailly and Daley Blind but he was not entirely convinced by any of them.
He drew up a shortlist of three targets and he told the club to sign one of them. The three names on the list in alphabetical order were Michael Keane, Victor Lindelof and Virgil van Dijk.
On June 15, United agreed a deal with Benfica to sign Lindelof for £31m and six months later Liverpool paid Southampton £75m for Van Dijk.
10. Alan Shearer
Not many players turn down Manchester United outright. Alan Shearer did it twice.
The first snub came when he left Southampton for Blackburn in 1992 and again four years later when he signed for Newcastle.
United were told in 1996 that Shearer wanted to come to Old Trafford and his goals would have made a side who had just won the double again even better.
Talks were held with Shearer and his agent. All seemed to be going well until Shearer's agent called Ferguson and told him they had decided to sign for Newcastle instead.
Ferguson licked his wounds by going on a shopping spree. He bought Ronny Johnsen, Jordi Cruyff, Karel Poborsky, Raimond van der Gouw and a young Norwegian striker called Ole Gunnar Solskjaer.
Solskjaer went on to win six titles, two FA Cups and the Champions League at Old Trafford. Shearer scored 148 times for his boyhood club but won nothing for them, though he insists he has no regrets about turning down United.
9. Eden Hazard
Eden Hazard should have become a United player in 2012. It was nailed on, right until he signed for Chelsea for £32m.
Manchester City and Tottenham wanted to sign him from Lille as well, but Hazard says he chose Chelsea after speaking to Didier Drogba and Joe Cole.
Others are not so sure. Ferguson said the asking price had been too high and United had refused to pay Hazard's agent £6m to get the deal done.
Hazard went on to become one of the best foreign players in English football and he stayed at Stamford Bridge for seven seasons before moving to Real Madrid in a £130m deal last summer.
As for United, after missing out on Hazard they signed Shinji Kagawa from Borussia Dortmund.
8. Robert Lewandowski
Robert Lewandowski guarantees goals and if things had turned out differently he would have spent his weekends celebrating at Old Trafford instead of the Allianz Arena.
According to Lewandowski, he spoke to United in 2012 and was impressed by what he heard, but Borussia Dortmund refused to let him go. And who can blame them, the Poland international had just scored 30 times to help them win their second consecutive title under Jurgen Klopp.
Lewandowski eventually joined Bayern Munich two years later and has since scored 230 times and won the Bundesliga five years in a row.
7. Patrick Vieira
Alex Ferguson always wanted to sign the best players and that included the captain of one of his fiercest rivals.
United tried to sign Patrick Vieira in 2001 and 2003 but it was always a long shot. Ferguson believed Vieira wanted to make the move and there was talk of a £22m deal after David Beckham was sold to Real Madrid in the summer of 2003.
A deal may have been on the cards because Vieira had only a year left on his contract at Highbury, but United fans were not getting carried away, and with good reason.
On August 12, Arsenal announced their captain had signed a new four-year contract said to worth £70,000-a-week.
6. Rivaldo
There was something in the air in the summer of 1999. United had just won the treble and there was talk of Rivaldo coming to Old Trafford.
Rivaldo had won the Ballon d'Or and the FIFA World Player of the Year award at Barcelona but his relationship with their manager Louis van Gaal was not great.
However bad the problems were though; they weren't bad enough for Barcelona to consider selling their best player to one of their European rivals.
"There has never been an occasion when Barcelona have been prepared to sell," Ferguson said.
5. Gabriel Batistuta
Gabriel Batistuta. What a player. What a man. He looked like Jon Bon Jovi and he scored some of the best goals you will ever see.
During the '90s he was continually linked with United, and every other big club in Europe for that matter. But despite all the interest he stayed at Fiorentina for nine years until he moved to Roma in 2000.
Batistuta was at the height of his goalscoring powers when Serie A games were shown live in the UK. You didn't need to be an international scout to see how good he was, you just had to switch on Channel 4 on Sunday afternoons.
Ferguson loved him and United tried to sign him, but the numbers being quoted were astronomical.
Years later, Batistuta was asked why he didn't move to a bigger club such as United, Real Madrid or AC Milan when he had the chance. "I preferred the tranquillity of playing for Fiorentina," he said.
4. Paul Gascoigne
It is one of the biggest imponderables of the English game. What if Paul Gascoigne had signed for Manchester United instead of Tottenham?
Would Fergie have been able to stop Gascoigne drinking during and after his career? Would Gascoigne have won it all and become an even better player than he turned out to be?
Who knows? What we do know though is that Alex Ferguson tried to sign him in 1988. Gascoigne was only 20 and even though he had not played for England yet, his advisers wanted him to be the best-paid player at United on £2,500-a-week.
That was never going to happen but after face-to-face talks Ferguson was confident he had convinced Gascoigne to sign for United. It was only while he was on holiday - allegedly reclining by the pool - that Ferguson received the news he had been dreading.
Gascoigne had met Spurs manager Terry Venables while Ferguson was in Malta and the meeting had gone well. So well that Gascoigne decided to sign for Spurs.
"They signed him by buying his mum and dad a house in the North East," Ferguson said. "Losing out on him was the biggest disappointment of all."
3. Ronaldinho
2003 was a strange summer if you were a United fan. David Beckham had been sold to Real Madrid and United were apparently close to signing Brazilian sensation Ronaldinho.
The only problem was that Barcelona were desperate to sign him as well after missing out on Beckham, and it was no surprise when he was seen juggling the ball at the Nou Camp after a €30m deal had been agreed with Paris Saint-Germain.
All was not lost for United though. Later that summer they signed Cristiano Ronaldo from Sporting Lisbon and they even managed to buy a Brazilian as well - Kleberson.
2. Zinedine Zidane
It was obvious that Zinedine Zidane would be leaving Bordeaux in the summer of 1996. He had just become Player of the Year in France and he was being watched by scouts from all the biggest clubs in Europe.
United had him on their list of targets and Eric Cantona told Ferguson that he should sign him.
According to former United chairman Martin Edwards, United didn't make a move for Zidane because Ferguson thought he was not what they needed at the time.
Zidane left Bordeaux that summer and went on to win some of the game's biggest trophies with Juventus, Real Madrid and France.
1. Ronaldo
The phenomenon. The original. Ronaldo had it all - pace, power, skill and devastating finishing. United were interested and they were offered the chance to buy him in 1996. The only catch was PSV Eindhoven wanted £20m.
That was crazy money for the time, though not crazy enough for Barcelona. They paid up, Ronaldo scored 47 goals in his first season at the Nou Camp and he went on to become one of the greatest players of all time.
United fans meanwhile had to wait another seven years before they got to see a Ronaldo in a red shirt. He turned out to be even better than the Brazilian one.