Leeds 1-1 Chelsea
Chelsea clung to top spot in the Premiership and Leeds moved off the bottom after an entertaining draw at Elland Road.
A superb individual goal from Jermaine Pennant gave Leeds an early lead against the leaders.
It was Pennant's first goal in 13 Premiership games since he joined Leeds on loan from Arsenal and the first time Chelsea had conceded in the league since 18 October.
Leeds harried Chelsea's expensively assembled squad throughout the afternoon but, after a frustrating first half for the visitors, Claudio Ranieri's forced Paul Robinson into numerous superb saves before Damien Duff eventually equalised.
And with Arsenal conceding a late equaliser at Leicester, a draw was enough to keep Chelsea top of the Premiership.
Chelsea, looking to stretch their unbeaten run to 11 games, had the first chance of the match.
Adrian Mutu passed for Jimmy Floyd Hasselbaink to shoot at goal after 10 minutes, but the Holland international scuffed his shot and Robinson comfortably saved.
Leeds then opened the scoring in spectacular fashion.
Pennant dispossessed Claude Makelele and dribbled past William Gallas and Wayne Bridge before lifting the ball over Carlo Cudicini from eight yards.
Leeds continued to pack the midfield and try to suppress Chelsea's fluent passing, but Joe Cole and Hasselbaink combined to create space for Lampard.
The in-form midfielder drove from the edge of the area but his shot was tipped around the post for a corner.
Leeds made the most of their few first-half chances and, after a superb lay-off from Mark Viduka, Stephen McPhail was inches away from doubling his team's lead with a side-footed shot.
Ranieri introduced Hernan Crespo for Joe Cole at the start of the second half, taking the game to Leeds with a three-pronged attack.
And Robinson was soon in the thick of the action, denying Duff just minutes into the second-half.
The Leeds goalkeeper made a double save to deny Mutu and Crespo, with Dominic Matteo then making a crucial block after the ball had fallen to Duff.
18 mins: Pennant scores a brilliant goal
56 mins: Robinson saves from Mutu and Crespo
70 mins: Duff equalises
But Chelsea's pressure was eventually rewarded with a goal.
Another shot from Mutu was saved by Robinson but the rebound broke for Duff to equalise.
Leeds refused to buckle after conceding and, with Didier Domi and Seth Johnson replacing McPhail and James Milner, Eddie Gray's team restricted Chelsea's openings.
And Viduka might have snatched an unlikely win, but made poor contact with an Ian Harte cross and his tame headed drifted wide.
Leeds: Robinson, Kelly, Radebe, Duberry, Harte, Pennant,
Matteo, McPhail (Domi 64), Smith, Milner (Seth Johnson 63),
Subs not used: Carson, Morris, Bridges.
Booked: Smith, Radebe, Matteo.
Chelsea: Cudicini, Melchiot, Terry, Gallas, Bridge, Makelele,
Lampard, Cole (Crespo 45), Duff, Hasselbaink (Gronkjaer 74),
Subs not used: Sullivan, Desailly, Geremi.
Booked: Hasselbaink, Mutu.
Referee: M Dean (Wirral).