Just hours after Paul Scholes headed Manchester United back into title contention with an injury-time winner at Eastlands, goals from Jermain Defoe and Gareth Bale denied Chelsea a response - boosting Tottenham's own Champions League ambitions in the process.
A bad day for Chelsea turned dreadful when captain John Terry was sent off 13 minutes from time, and Frank Lampard's late goal was little consolation in a game that Spurs dominated.
Carlo Ancelotti's side now hold a one point lead at the summit of the Premier League, with three games remaining. Spurs, on the other hand, are now two points ahead of Manchester City and take over as favourites in the race for fourth.
In stark contrast to the Manchester derby earlier in the day, the clash between these two London rivals at White Hart Lane was full of quality and excitement from the very start.
Fresh from a stunning series of saves in Tottenham's 2-1 victory over Arsenal on Wednesday night, Heurelho Gomes was the first goalkeeper forced into action, palming away Florent Malouda's stinging strike from distance.
The hosts, however, appeared to have the extra bounce in the early stages, particularly through explosive surges down the left by Bale.
The Welshman brought a huge shout for a penalty on 13 minutes when he was too quick for John Obi Mikel and appeared to be fouled. Chelsea got away with it on that occasion but a minute later referee Phil Dowd was pointing to the spot.
David Bentley whipped in a cross that Roman Pavlyuchenko flicked onto the arm of Terry, who had no complaints. His England team-mate, Jermain Defoe, stepped up to slam home his 24th goal of the season.
Malouda appeared to have poked in a leveller for Carlo Ancelotti's side in the 38th minute but the French winger was correctly ruled to have been in an offside position.
To make matters worse, Tottenham doubled their advantage just before half-time through Bale's fine effort. After being put through down the left by Pavlyuchenko, he cut inside the struggling Paulo Ferreira and fired into the near corner with his weaker right foot.
Ancelotti responded to a lacklustre opening period by bringing on Branislav Ivanovic and Nicolas Anelka, completing his full set of changes after Mikel was forced off during the first-half due to injury.
The second period, however, started in the same fashion, with the excellent Cech bravely denying Defoe five minutes after the re-start as Tottenham's top scorer charged through on goal.
The anticipated Chelsea onslaught did not arrive and the Blues' awful day was capped off in three second-half minutes as Terry made reckless challenges on first Pavlyuchenko and then Bale to bring two yellow cards.
Bentley then watched his nonchalant lob tipped over by Cech.
Bale poked wide and Pavlyuchenko missed a sitter as the hosts cut Chelsea to ribbons but could not score a third. Frank Lampard stabbed in for Chelsea in added-time but the day belonged to Tottenham - and Manchester United.