Manchester United appeared firmly in control for 20 minutes, but substitutions helped Chelsea get back into the game.
Sir Alex Ferguson recalled Wayne Rooney, using him behind Javier Hernandez, with Shinji Kagawa left and Nani right. Jonny Evans also returned.
Rafael Benitez surprisingly named Ramires and Frank Lampard in midfield, allowing him to play three attackers, including Victor Moses, behind Demba Ba. Cesar Azpilicueta was at right-back.
United took an early lead with goals from Hernandez and Rooney, but then seemed to stop playing – and Chelsea could have won it late on.