Chelsea – Premiership champions 2009/10. A great side? Probably not, but it’s hard to argue that, over the course of the season, they do not deserve to lift the trophy.

In terms of the players who have started the greatest number of matches, Chelsea’s XI this season reads: Petr Cech (34); Branislav Ivanovic (21), John Terry (37), Ricardo Carvalho (22), Ashley Cole (25); Jon Obi Mikel (21), Michael Ballack (26), Frank Lampard (36), Florent Malouda (25), Nicolas Anelka (31) and Didier Drogba (31).

And yet, on only one one occasion this season has that XI actually started a match together, in the 2-0 home victory over Arsenal in February, when Ancelotti fielded a Christmas Tree formation with Anelka and Malouda playing Didier Drogba.

That system has not been the regular system for Chelsea throughout the season, however. Indeed, Chelsea have won the league despite it being difficult to identify Carlo Ancelotti’s first-choice XI, or even his first-choice formation.

He began the season with a diamond midfield – something rarely seen throughout Premiership history – as Chelsea threatened to run away with the title. They won twelve of their first fourteen games with a cumulative score of 37-8.

The main problem with the diamond shape though, as always, was its lack of width. Neither Anelka or Drogba is particularly comfortable drifting wide, whilst Florent Malouda playing ‘from in to out’ doesn’t have the effect fielding a natural winger does.

The natural solution, therefore, was for the full-backs to get forward to provide width, and Ashley Cole and Jose Bosingwa’s pace and energy meant Chelsea could afford to play a narrow midfield. Boswingwa’s season-ending injury in mid-October was a big blow to the diamond, however (until then he had started every game) as Ancelotti was forced to turn to Branislav Ivanovic at right-back.

Ivanovic is an excellent defender and has had a very good season, but doesn’t offer the attacking threat of Bosingwa. Having spent much of the season at right-back, he has improved on the ball, but initially he didn’t work with the diamond. This weakness in Chelsea’s system was exposed when Manchester United visited Stamford Bridge, as Sir Alex Ferguson deployed Antonio Valencia high up the pitch to nullify Ashley Cole, with Ryan Giggs tucked in on the other side. This meant that United could match Chelsea’s diamond AND prevent the threat from left-back with a right-winger, leaving one striker up the pitch. Ivanovic was free and had time to advance, but he was not as much of an attacking threat as Bosingwa would have been, and Ferguson was happy for him to have the ball. United dominated the game, and were unfortunate to lose.

ZM said at the time that Chelsea won that match despite – rather than because of - the diamond, and that Ferguson had effectively found it out. Soon after, Chelsea hit problems – a draw at home to Everton, a loss at Manchester City, a draw away at West Ham, a draw at Birmingham – and late 2-1 wins over Fulham and Portsmouth. Jack Collison and Shaun Wright-Phillips played Valencia-esque roles against Ashley Cole, and Chelsea continued to struggle for width. Two narrow wins from six games was not title-winning form, even if they still started the new decade on top of the league.

The Africa Cup of Nations was held up as something that might derail Chelsea’s season, but it turned out to be crucial in keeping them on top. The absence of Drogba (and Saloman Kalou) meant Chelsea didn’t have the resources to continue with a two-striker system, and so Ancelotti reverted to a ‘christmas tree’ shape, with Joe Cole and Florent Malouda floating behind Nicolas Anelka. They barely missed Drogba in wins over Sunderland, Birmingham and Burnley, and the Cole-Malouda-Anelka trident would later guide Chelsea to important wins, including the ultimately crucial 1-2 victory at Old Trafford, and the crushing 7-1 win over Aston Villa.

The final third of the season saw Ancelotti playing various shapes – the diamond, the christmas tree, and a 4-3-3 / 4-2-3-1 – and it often appeared he wasn’t quite sure of his best system. This was a problem against a well-drilled, efficient Inter side, and Chelsea were deservedly beaten home and away.

In the Premiership, however, Ancelotti could get away with the constant switches because the defensive base of the side remained the same. It always featured a back four, and always featured (at least) three midfielders who started from the centre of the pitch. Whether the three forwards were arranged in a wide system or in a more narrow setting didn’t make too much difference to how Chelsea’s defence operated. We never saw a three-man defence, or a traditional four-man midfield, and Ancelotti was rigid in the fact he always played a back four supplemented with three central midfielders – in this sense similar to how Mourinho’s Chelsea operated.

Further forward, Ancelotti was able to adapt the shape to suit the game – and suit his on-form players. Malouda, Drogba and Lampard all peaked at different points in the season, and all preferred slightly different formations. Whichever system Chelsea played, it always brought the absolute best out of one of those three – Malouda and Drogba played their best football in a Chelsea shirt, whilst Frank Lampard ended the season with 14 goals in 11 games.

Admittedly, the flipside of this was that Chelsea didn’t really find a system that completely suited their two creative players (Lampard and Malouda) as well as their two strikers (Drogba and Anelka) at the same time. In the diamond, Lampard’s midfield runs were restricted and Malouda was playing too centrally, but Drogba and Anelka were on fire. In the 4-3-2-1, Anelka struggled behind the frontman and Drogba’s link play wasn’t great, but Lampard and Malouda were in their element. The system worked better with Anelka upfront, and Drogba benched, as against Manchester United.

Ancelotti never found a system that suited all four, so Chelsea relied on individual brilliance in the final third rather than a genuinely cohesive shape. Often this worked brilliantly – recording 7-2, 7-1, 7-0 and 8-0 victories in the final four months of the season. When one player didn’t provide inspiration, however, they suddenly looked completely out of ideas, as the two defeats to Inter, the 2-4 loss against Manchester City and the limp 2-1 defeats away to Everton and away to Tottenham showed. But maybe, when your two strikers are Anelka and Drogba – hardly the definition of ‘team players’ – you have to bring the best out of the individuals rather than worry too much about the combination play.

They ended the system with something more like a 4-2-3-1 (as against Liverpool) which was ruthless and looked unstoppable, but this wouldn’t have been an option throughout the season – a central midfield partnership of Lampard and Ballack would surely have struggled against the genuinely top sides in the Premiership and Champions League.

In all, Chelsea deserve the title, even if crucial, incorrect refereeing decisions in both victories over Manchester United can be pinpointed as fortunate moments. Ancelotti becomes just the fifth manager in Premiership history to win the title, and records only the second league victory of his career.

A common criticism of struggling managers is that they ‘don’t know their best eleven’, but with this victory, Ancelotti has proven that you don’t always need to.

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