Barcelona are hoping to pull off a sensational deal to re-sign Neymar from Paris Saint-Germain, but how will they fit him into the same team as Lionel Messi, Luis Suarez, and new signing Antoine Griezmann?
They have bid £90m plus two players for Neymar, according to Sky Sports News, giving PSG the chance to sign Philippe Coutinho, Ousmane Dembele, Ivan Rakitic, Nelson Semedo, Malcom, or Samuel Umtiti as part of the deal.
PSG are believed to be demanding £200m, the same amount they paid for him in 2017, but there is a willingness to make the deal happen on both sides, with PSG boss Thomas Tuchel admitting on Wednesday that he has been aware of Neymar's desire to leave since the start of the summer.
Why do Barca want him back?
With 51 goals in 58 games, Neymar boasts an impressive scoring record for PSG. But the numbers do not tell the full story. The 27-year-old has missed large chunks of action due to injuries and other absences, with his work rate and professionalism repeatedly questioned. There have been clashes with teammates and coaches, and the club's patience has finally run out.
Barcelona are, of course, aware of the baggage Neymar brings. And on top of that, they must also consider the lingering bad blood from his exit two years ago. Barcelona were sure he was staying - Gerard Pique infamously announced it on social media - only for him to leave them in the lurch a week before the season began. A legal dispute is said to be ongoing.
The other side of it, though, is that they also know just how good he can be.
Neymar scored 105 goals in 186 games for them, playing a crucial role in their 2014/15 Champions League triumph and forming a devastating understanding with Messi and Suarez. In 2017, he was the inspiration behind the extraordinary Champions League comeback against PSG.
It is also important to remember that Barcelona never wanted to let him go in the first place. Neymar combined brilliantly with Messi, but he was also viewed as the Argentine's long-term successor. With Messi now 32, Neymar's time to take centre stage could be drawing closer.
Without Neymar, Barcelona have become overly reliant on Messi and Suarez for goals. Their overall total of 90 in La Liga last season may have been considerably higher than any of their rivals, but it was in fact their lowest since 2007/08. Between them, Dembele and Coutinho contributed fewer goals and assists than Neymar managed on his own in his final season.
How would they line up?
Neymar would walk straight back into Barcelona's starting line-up, but Antoine Griezmann, at 28 years old and at a cost of £108m - a fee Atletico Madrid are still disputing - has not arrived to sit on the bench.
The prospect of Neymar and Griezmann lining up in the same team as Messi and Suarez is a tantalising one, but how exactly will Ernesto Valverde fit them all in?
During Neymar's previous stint at the club, Barcelona lined up in a 4-3-3 formation, with a midfield of Ivan Rakitic, Sergio Busquets, and Andres Iniesta behind the MSN front three. Neymar started on the left, with Messi on the right, and Suarez through the middle.
Valverde generally used the same shape last season - only with Coutinho or Dembele in place of Neymar, and Arthur or Arturo Vidal replacing Iniesta. In order to squeeze Griezmann in too, though, he will have to adjust.
Could he opt for a 4-2-3-1 formation? New signing Frenkie de Jong would be the obvious candidate to partner Sergio Busquets at the base of midfield, which would then allow Griezmann, Messi, and Neymar to play behind Suarez.
That would mean a new role for Griezmann, who played centrally for Atletico Madrid, but the Frenchman is also comfortable on the right. Messi, meanwhile, is already dropping deeper than he did earlier in his career, allowing him to influence games with his passing as well as his goals.
Neymar, then, would effectively be playing the same left-sided role as he previously did for Barcelona. What can go wrong?
Will it work?
It certainly looks good on paper, but whether this star-studded Barcelona attack would actually work in practice is another question.
Between them, Messi, Suarez, Neymar, and Griezmann have scored close to 1,700 career goals. They are all, in different ways, a nightmare for opposition defenders. But it is fair to say none of them excel defensively. Could Valverde convince them to track back and help out their teammates?
It is more likely that the rest of his team would have to pick up the slack.
An enormous amount of work would fall to Busquets and De Jong in central midfield, and it might also be necessary to curb the attacking instincts of the full-backs. Jordi Alba loves to charge forward on the overlap, but with four out-and-out attackers already on the pitch, Barcelona would risk leaving huge gaps at the rear.
It would be possible, of course, to simply outscore most of their opponents in La Liga, but that approach would carry considerable risks in the Champions League, where an imbalanced team can be ruthlessly exposed by organised, top-level opposition.
There are lessons to be learned from Real Madrid's Galactico era, when they spent huge sums bringing a long line of the world's most revered attackers to the Bernabeu with the intention of blowing their opponents away.
The approach was successful at first, yielding two La Liga titles and a Champions League triumph between 2001 and 2003, but it all went awry after that. The egos in the dressing room proved problematic, and Real Madrid began to look more like a selection of individuals than a team.
"I don't regret bringing the best players in the world to this club," reflected Madrid president Florentino Perez later. "But perhaps I wasn't able to make them understand the importance of their responsibilities. Maybe I educated them badly."
The challenge for Barcelona would be to avoid those same pitfalls. A front four of Messi, Suarez, Griezmann, and Neymar would guarantee excitement. But a guarantee of excitement is not necessarily a guarantee of success.
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