The back three has never been more en vogue in the Premier League.
Not since the 1980’s and early 1990’s - most often on the continent and at international level - when the sweeper system became popular, have we seen so many sides play with three central defenders.
Gradually the system has crept back in and now several teams use three central defenders in their primary formation.
Here we’re looking at what the changes mean, how those teams have fared and whether or not it’s here to stay.
The biggest of changes
As any Football Manager or FIFA enthusiast (the EA game, not football’s governing body) will testify, there are dozens of formations in football.
However, three central defenders versus a back four (two central defenders) is the biggest or most dramatic formation switch you can make. 4-4-2 and 4-3-3 are different but with a support striker possible in both and two full-backs as well as two wide players further forward intact, they can transition quite easily.
In any of the back three systems a manager can select, there are anywhere between six and nine outfield players fulfilling a different role to 4-4-2, for example.
So far this season, ten Premier League teams have used a system which incorporates three central defenders.
Occasionally that has meant a back five but more often than not we have seen wing-backs used, with starting positions in line with the midfield.
Why the change?
Football does go through periods where successful sides are copied and teams match up.
Before Jose Mourinho’s Premier League arrival in 2004, few sides played with one central striker but from that point on it dominated right across the league with 4-4-2 seen as archaic by many.
Antonio Conte has played with three central defenders almost exclusively over the past five years - with Juventus, Italy and now Chelsea.
He began at Chelsea sticking with the 4-3-3 that the club have used for over ten years but has made the alteration and not switched back since.
Watford’s Walter Mazzarri used three central defenders just as frequently in his last role as Inter Milan boss in 2013-14 and for four years at Napoli from 2009 to 2013 too.
On that basis, it’s actually surprise that Conte began with a back four and that Mazzarri has switched between two systems throughout the opening 17 games.
Pep Guardiola had often switched between systems at Barcelona and Bayern, whilst Ronaldo Koeman used a back three at Southampton and Feyenoord on occasion.
Slaven Bilic has used a back four throughout most of his managerial career and so his switch might be a surprise, whilst the rest of the managers have only really flirted with using it - even if it is unusual based on their past.
The story so far
It’s a very small sample size and the variation of fixtures - difficulty and home or away - does make it difficult to read too much into.
It at least gives you an insight into how much some teams have used and switch between systems.
Chelsea have won every single game since switching to a 3-4-3. It’s worth mentioning that Chelsea have only lost two games though and those were to Arsenal and Liverpool.
Would the system have mattered?
Manchester City’s stats might suggest the players have not adapted to that system when asked to. Again, small sample size and they’ve lost to Chelsea with three and Tottenham with four at the back. They’re probably just inconsistent.
Hull, Swansea and Sunderland are certainly inconsistent.
Chelsea’s success
Using three central defenders is an ideal system for teams looking to dominate possession.
Teams that expect to control games can use it to have plenty of the ball, build from the back and often create overloads and spare players in every area of the pitch.
Centre-backs should be comfortable with plenty of possession and wing-backs should not only be physically fit but show a mentality and ability to attack and defend in equal measure.
In the front areas, either natural wide players are freed of defensive responsibility and can go and create like Eden Hazard in Chelsea’s 3-4-3, or the forwards should be adept at playing in a front two, like Troy Deeney when Watford have used a 3-5-2.
In respect of having players who fit the system, Chelsea tick every box.
Apart from an energetic coach who demands the same from his players, they all fit into Antonio Conte’s system very well.
Many would have expected the back three to be made up of Gary Cahill, David Luiz and John Terry, with perhaps Cesar Azpilicueta and Marcos Alonso as wing-backs.
In pre-season, there was a suggestion that Branislav Ivanovic may play as a wing-back too, having seen the Serbian fly forward and grab goals and assists down the years.
I don’t think too many expected Azpilicueta - who has excelled for the past three years at left and right-back - to be moved back into central defence.
The Spaniard could probably play in goal though, he’s that technically gifted and tactically adept.
N’Golo Kante might become the first player to win back-to-back league titles with two different clubs since Eric Cantona in the Division One-Premier League crossover and Chelsea’s Frenchman is ideal in a central midfield pairing - something which can’t be said of every midfielder these days.
Hazard and Pedro, along with Willian, have been allowed to roam free and it helps that Thibaut Courtois is excellent, whilst Diego Costa is in his best form since arriving at Chelsea, too.
Is three at the back here to stay?
Chelsea’s eventual success could be a deciding factor.
The success they’ve enjoyed until now could see the system replicated anyway but otherwise, for the reasons above about how the systems must work, it probably shouldn’t.
Unless a club and manager prepare to play this way, it is hard to do it across a season because you would need to invest in the right areas - for a start, you need enough centre-backs to cover absences, not to mention wing-backs who understand what is expected of them.
Watford did actually prepare for the system (unsurprising given Mazzarri’s history using it) by signing depth at centre-back, full-backs who like to get forward and a selection of centre-forwards.
Otherwise it’s a system that quite difficult to switch to game-to-game.
Whatever the predicament, it won’t stop managers experimenting and tinkering when they need to and if three at the back is in fashion, expect them to turn to it.
I don’t see many using it over a long-term period but if Mark Hughes has been tempted, perhaps it is here to stay.
The results to this point, Chelsea aside, don’t look too promising though.
Written by Richard Clark
Follow Richard on Twitter @richardtheclark
Check out his excellent football blog, Blog of the Net and follow them on Twitter @BlogOfTheNet
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