Andre Villas-Boas' Tottenham drew 2-2 at Stamford Bridge on Wednesday evening, and, in doing so, sustained a huge blow in their quest to finish in the top four.
Oscar opened the scoring for Chelsea, but a golazo from Emmanuel Adebayor pegged them back. The Blues continued to probe and were eventually rewarded when Ramires' prodded effort found the back of the net.
In the second half, Chelsea were largely dominant, but a deft flick from Adebayor allowed substitute Gylfi Sigurdsson to curl one home from inside the box.
Gareth Bale had a last-minute chance to win it, but his free kick was plucked out of the air by Petr Cech.
The game was billed as "must-win" for Spurs, who required a three-point haul to keep the chase for UEFA Champions League football in their own hands
But the away side started slowly and were clearly feeling the absence of Mousa Dembele in midfield, misplacing passes and failing to get their front men into the game.
The pressing game Chelsea employed was superb, and dogged attention from the likes of Oscar, Juan Mata and Fernando Torres put Scott Parker and Tom Huddlestone under severe pressure.
After 10 minutes, Spurs had created nothing and gave away their first corner under pressure from Branislav Ivanovic.
The ball was swung in, Gary Cahill nodded it on and Oscar finished from close range at the far post. It was a cute finish, but Parker was guilty of letting his marker go.
The Blues continued to flood the attacking third and placed Tottenham's holding midfield pivot under extreme pressure, but despite the home side looking good value for another goal, the away side hit them on the counter.
A Chelsea corner was cleared, and Adebayor picked it up. His long, loping stride took him out of his half, and when no challenge came, he simply continued.
Aaron Lennon's clever run to his left stopped Cesar Azpilicueta from closing him down, and the Togolese hit man unleashed a beautiful curled strike from 25 yards to level matters.
Undeserved, but Chelsea were not deterred—they continued to press high and found a weakness in Benoit Assou-Ekotto.
Super buildup play pulled Jan Vertonghen out of position, and Ramires powered into the space vacated and tipped the ball home.
The second half start started brightly as far as the home side were concerned, but the fourth and final goal was to be Spurs': Sigurdsson's wrapped finish was sublime and breathed new life into a flailing side.
A tense finale saw both teams slug away at each other, and Chelsea will be the much happier side when they check the table again.
It's out of Spurs' hands—they are relying on an Arsenal slip-up. Should the Gunners win their remaining two fixtures (Wigan at home, Newcastle away), a top-four slot is guaranteed.
Despair for AVB and Co.