A Gus Poyet double helped Chelsea end Manchester United's 29-match unbeaten Premier League run with a 5-0 hammering at Stamford Bridge.
Poyet put the Blues ahead with a header after only 27 seconds before Chris Sutton headed in his first Premier League goal for the hosts.
Man Utd's Nicky Butt was sent off for tangling with Dennis Wise before the break, and Poyet stretched Chelsea's lead in the 54th minute with his second.
Henning Berg turned Gianfranco Zola's cross into his own net for the Blues' fourth before Jody Morris completed the scoring.
United, on 21 points, lost top spot to Leeds United, while Chelsea moved up two places to fourth with 19 points.
Luke Varney was the matchwinner for Premier League new boys Blackpool as they beat under-pressure Liverpool 2-1 at Anfield.
Charlie Adam put them ahead with a penalty after a foul on Varney, who doubled the lead with a powerful shot in first-half stoppage time.
Liverpool, who lost Fernando Torres to injury after 10 minutes, battled back and Sotirios Kyrgiakos headed in a Steven Gerrard free-kick in the 53rd minute to give them hope.
But Blackpool held on to climb seven places to ninth in the table with 10 points, while Liverpool stayed in the bottom three on six points.