After Manchester United's relatively successful experimentation with a narrow diamond midfield this season (see Michael Cox analysis of their 3-0 win over Newcastle), Sir Alex Ferguson opted for his more traditional 4-4-1-1 shape against Chelsea with two true wide players in Ashley Young and Antonio Valencia.
His decision to go with width against Chelsea wasn't a particularly difficult one. Ferguson knew full well that his counterpart Roberto Di Matteo would go with the 4-2-3-1 system- with Oscar, Juan Mata and Eden Hazard forming the attacking midfield three- that Chelsea had enjoyed success using in the league this season. Since Chelsea used the formation for the first time in a 2-2 Champions League draw against Juventus, they have employed the same attacking midfield three behind Torres in every Premier League game. Ferguson had plenty of chances to scout the formation and would have had little difficulty recognizing its weaknesses.
Chelsea's 4-2-3-1 formation has two main weakness. The first weakness is its vulnerability to counter attacks (particularly down the flanks). When Ashley Cole and Branislav Ivanovic push forward to help the attack, space opens up in wide areas for the opposition to quickly move into on the break. The second weakness is its tendency to leave Cole and Ivanovic without cover in wide defensive areas. Neither Mata nor Hazard are especially keen defenders. Hazard is particularly guilty of failing to offer defensive cover to his outside backs. Against teams that play with narrower midfields this isn't always a huge problem because John Obi Mikel and Ramires provide cover for the back four in the center of the pitch in their deep lying midfield positions. However, against teams with wingers the problem becomes more apparent. With Mata and Hazard staying high up the pitch, space often opens up for opposition outside backs to advance past them unchecked. When the opposition outside back receives the ball, it leaves Chelsea's own outside back overloaded and forces him to try to defend two players. He's forced to step to ball, leaving the winger unmarked with the time and space to receive the ball and play dangerous crosses into the box.
That United's two early goals came from exploiting these two Chelsea weaknesses suggests Ferguson got his tactics about right. The first goal came when United were able to nick possession in midfield and counter quickly down the right. The second came when United right back Rafael was able to receive the ball behind Hazard, creating a 2 v. 1 advantage with Valencia down the right wing for United. Cole was forced to leave Valencia unmarked and step to Rafael. The Brazilian played a simple ball wide to Valencia who had the time to pick out Van Persie's run in the box (I unfortunately can't embed the video but you can watch the goal on YouTube here). Had Hazard been more diligent in his defensive responsibilities, Rafael would have never received the ball as high up the pitch as he did.
It should be interesting to see how United line up against Arsenal this weekend. Like Chelsea, the Gunners have almost exclusively played a 4-2-3-1 this season and therefore face some of the same defensive problems as Chelsea (although Lucas Podolski and Aaron Ramsey seem to do a slightly better job of protecting their outside backs than Mata and Hazard). Will Ferguson once again opt for a 4-4-1-1 and try to exploit space on the wings? Since Arsenal have been forced to play Andre Santos at left back for the injured Kieran Gibbs, they have looked very vulnerable to attacks down the opponent's right side. It would be surprising if Ferguson didn't again opt for a right winger to exploit the shaky Santos.
Chelsea's and Arsenal's continued use of a 4-2-3-1 indicates the players are comfortable in that system and with each game they play in that system they'll continue to develop a better understanding of one another and become more fluid. However, it also makes them predictable for clever, adaptable managers like Ferguson who are happy to play reactive football. The Scotsman is comfortable playing any number of different formations and styles based on the strengths and weaknesses of his opponent. More often than not, when he knows how the opposition is going to set out to play, he can implement a strategy that gives United a very good chance of winning games. I'm not suggesting Arsenal and Chelsea should alter their formations from time to time in the same manner as Ferguson. Playing Ferguson's more reactive style has its own draw backs, mainly that by adapting your formation to your opponent you aren't able to develop a fluid, consistent system of your own and sometimes even managers with the pedigree of SAF simply get the tactics wrong. United's 1-0 defeat to City at the end of last season that effectively handed the league title over to City is a good example. Ferguson set out with Park Ji Sung as the most advanced midfielder behind Rooney in a 4-5-1 in a set up designed to attack on the counter. Park was forced to track Yaya Toure's runs forward, leaving Rooney isolated up top. United rarely threatened after going a goal behind. However, more reactive managers do have the distinct advantage of arranging their teams to mitigate the most dangerous elements of an opponents system and exploit the weakest ones.
It should also be mentioned that Ferguson's tactics against Chelsea were hardly flawless. After going up 2-0, Chelsea were much the better side until being reduced to 10 (then 9) men. During this stretch of the game Chelsea out passed United 220 to 156 and United were continually troubled by Chelsea's numerical superiority in the center of midfield. Perhaps Ferguson would have been wise to replace Young with someone like Anderson who would have allowed United to better compete in the center of midfield after going up by two goals.
