Friday 7 October 2016 19:54, UK
Since the Premier League's inception 25 years ago, English football has undergone some wholesale changes.
With hi-tech new stadia and talent recruited from around the globe, the face of football has changed but how have teams, and specifically their formations, altered over the years?
Modern systems require full-backs to provide defensive stability and attacking threat in tandem, a role in stark contrast to defence-orientated requirements of the past.
At the other end of the pitch, the days of formidable strike partnerships appear to have disappeared, replaced by the likes of Zlatan Ibrahimovic in the lone centre-forward position or Adam Lallana in the fashionable false nine role.
As part of Sky Sports News HQ's evolution of football week, Danny Higginbotham takes a closer look at the latest trends...
DANNY SAYS: This is still the best system, in my opinion. As long as it switches to 4-5-1 when out of possession it's a formation that can outdo anyone, Leicester City showed that last season.
The role of the full-backs is different in this system, at present we see full-backs play like wingers with both attacking at the same time. But historically when one full-back would attack the other would tuck in and make three at the back - if one full-back went, the other would not go.
DANNY SAYS: This is a more traditional modern-day formation. One of the teams who utilise this system well are Tottenham. What they do very well is attack with both full-backs, who are expected to play both left-back and left midfield at the same time.
Spurs transfer from defence to attack so quickly and the full-backs are key to that as they break into open space with pace. One second they're defending, the next the ball's in the back of the net.
The way that is done nowadays is down to the defensive side of things, teams want to maintain their defensive solidity when they're attacking.
This is achieved when the two centre-backs split and a midfielder drops back into the defensive line. Teams still have the strength that comes from having three at the back, meaning they're less likely to be counter-attacked.
This has completely changed the role of the full-back, they've got to be more athletic and fitter, because they're responsible for the length of the pitch in attack and defence.
DANNY SAYS: You used to see the big man and little man up front - Niall Quinn and Kevin Phillips for example - and you didn't really see centre-forwards isolated. As such the big man would occupy the defenders, allowing the little man to feed off knock-downs.
Dennis Bergkamp and Thierry Henry were another formidable Premier League partnership. They worked differently though, Henry would stretch the game and Bergkamp would drop deep.
Andy Cole and Dwight Yorke were telepathic with some of the goals they scored. They had a real understanding, they would always interchange positions.
Then there was Alan Shearer and Chris Sutton, another partnership that ensured neither striker was isolated because they had a partner.
With this formation, wide players, and the full-backs to some extent, would try and create a two-on-one against opposition wide players who loved going forward but weren't the greatest defensively.
We don't see a lot of goals being scored from crosses now but when there were two centre-forwards, and potentially a midfielder and winger from the opposite side, we did.
This was arguably down to the fact there were more out-and-out wingers plying their trade in the Premier League, but the fact centre-forwards were rarely isolated played a massive part.
DANNY SAYS: Nowadays with 4-3-2-1 we often see the centre-forward isolated and reliant on the three players behind him for support and to provide him with the opportunity to score goals. Zlatan Ibrahimovic is a good example of the modern-day lone centre-forward as he carries out both attacking tasks.
In the traditional formations, the smaller forward would work the channels but Ibrahimovic is often found stretching defences.
At other times he allows the three supporting midfielders to attack the space in front of him, allowing him to operate in behind, as seen with his goal against Bournemouth.
The role of the striker has changed along with formations. The notion of a centre-forward is to create a gap between the midfielders and the defence.
If you have a single centre-forward who wants to drop deep, the three midfielders behind him can push on into the space he has vacated. While if the forward holds a high line, that opens up space in the middle of the park for those behind him to play into.
DANNY SAYS: People talk about the false nine as though it was invented recently. Johan Cruyff actually brought it in at Barcelona in the late 80s and it was very successful.
Liverpool are one of the teams who use the formation really well at the moment, with no recognised centre-forward in the line-up.
Jurgen Klopp plays with two holders in midfield in Jordan Henderson and Georginio Wijnaldum and the four players in front readily interchange positions.
They have utilised the formation so well that they vacate the number nine area completely and, in recent weeks, Adam Lallana in particular has had free rein to roam into the position. It's all about the players off the ball creating space for runners from deep to run in to.
Ultimately, there are a lot of different tactical approaches and, with Premier League squads being so similar, a slight tactical change by managers could be the difference between winning and losing games.