Sang Tan/Associated Press
The basic game plans for these two sides could not have been more different. David Moyes knew his side needed to grab three points to catch up, while Jose Mourinho knew he was sitting pretty in the top three.
As always, the Chelsea victory was founded upon extremely defensive solidarity, and as Manchester United began to run out of steam, the Blues picked them off.
Mourinho defended with six or seven at all times, with special care taken to protect full-back Cesar Azpilicueta against the two-headed monster of Antonio Valencia and Rafael.
Although the Spaniard was beaten several times, you'll note that John Terry was very rarely dragged out from his central zone. Both he and Gary Cahill sat pretty in the middle, with other players dipping in to help defend the flanks.
That set up a solid platform for the Blues to deflect forced aerial assaults with ease, and from there one ball out to Willian or Eden Hazard—who played incredibly direct football—could drag the home side 50-60 yards up the pitch in five seconds.
Attack with four, defend with six. Every time.