SPURS won at Stamford Bridge for the first time in 28 years overnight, and in the process all but ended Chelsea's chances of nabbing a crucial top four finish with a 3-1 win.
Elsewhere, Arsenal closed the gap between themselves and the Blues to five points with a 3-0 victory over Stoke City.
Antonio Conte's side opened the scoring through Alvaro Morata before the visitors came flying back with three unanswered goals - including a double to midfielder Dele Alli.
Chelsea now trail fourth-placed Spurs by eight points with seven matches to play in the Premier League.
CHELSEA 1-3 SPURS
Cupping his ear to the Chelsea fans hurling abuse and flipping fingers, Dele Alli savored the moment.
Twice at Stamford Bridge on Sunday, inside four minutes.
With two goals, the Tottenham midfielder answered his critics and ended his team's 28-year victory drought at Chelsea.
By coming from behind to win 3-1 in west London, Tottenham extended its lead over Chelsea for the fourth Champions League place to eight points and left the Premier League champions facing a season out of Europe's top competition.
"I am sure people will still be disappointed with the way I have played," Alli said. "They will have plenty to say." If so, they'll lose sight of just how much Alli has already achieved while still so young.
Signed by Tottenham from Milton Keynes Dons in 2015 for only five million pounds (now about $7 million), Alli has 36 goals and 25 assists in 100 Premier League games.
"Sometimes we lose the focus that he is only 21 years old," Tottenham manager Mauricio Pochettino said, "and sometimes there is too much expectation on his shoulders."
The expectation was even greater on Sunday with top-scorer Harry Kane starting on the bench after three weeks out injured, and with Alli's recent struggles under the microscope.
Alli's place in England's World Cup squad was even questioned after playing just 22 minutes of two friendlies in the international break.
"He needs to win the trust and confidence of the national team manager again," Pochettino said.
"The only way to win trust and confidence is to play like he did today."
It was going to take something special to eclipse the exploits of Christian Eriksen, and to spare the blushes of Tottenham goalkeeper Hugo Lloris who flapped at a cross to allow Alvaro Morata to head Chelsea in front.
Eriksen's equalizer came in first-half stoppage time - a powerful, swerving strike from 25 yards.
"He's a magician with the ball," Alli said.
While Eriksen's shot flummoxed goalkeeper Willy Caballero, the pace and movement of the visitors troubled the entire Chelsea team in the second half.
A combination of Eric Dier's vision and Alli's technique sent Tottenham into the lead in the 62nd minute.
Dier launched a high ball from inside his own half over the Chelsea defense. Alli brought it down with one touch and used his second to lift the ball past Caballero.
Chelsea was reeling. The task got even harder after failing to close down a Tottenham counterattack in the 66th minute.
Dier and Eriksen broke forward and fed Son Heung-min, who cut in from the right and forced Caballero off his line.
The goalkeeper did block Son's route to goal but the South Korean recovered the ball.
Caballero made another intervention but Andreas Christensen failed to adequately clear and Alli pounced for his eighth goal of the season.
"He's so strong, he's a fighter, very competitive," Pochettino said.
"There is a lot of pressure on his shoulders. He has nothing to show to me or to us." It wasn't a sight Antonio Conte wanted to see. The Chelsea manager was left to kick water bottles in anger on the touchline.
"There was great frustration to concede a stupid goal in this way, instead of putting this ball in the stand," Conte said. "Maybe I wanted to play in that moment and to shoot the ball."
It encapsulated a season of irritation for Conte, whose last chance of silverware is in the FA Cup. Like Tottenham, Chelsea is through to the semifinals where it faces Southampton later this month.
"I don't want to create problems," Conte said, when asked to explain Chelsea's predicament - seemingly mirroring the decline after winning the title in 2015 with Jose Mourinho being fired.
Once again, the future of Chelsea's manager is very much in doubt. It seems unlikely even lifting a cup can save Conte, given the team's collapse from champions to sixth place with seven games remaining.
It was only 10 games ago that Chelsea was in second place and seven points ahead of fifth-place Tottenham.
Now after winning at Chelsea for the first time since Gary Lineker scored in a February 1990 game, Tottenham is in pole position to qualify for the Champions League for a third consecutive season.
And all the hard work was achieved with Kane on the bench. Tottenham's top- scorer only featured in the final 20 minutes after his right ankle made a rapid recovery from the ligament damage sustained three weeks ago.
"After 28 years to win again at Stamford Bridge, I think is a massive thing for our fans," Pochettino said.
ARSENAL 3-0 STOKE CITY
Arsenal broke through Stoke resistance with three goals in the last 15 minutes to win 3-0 in the Premier League on Sunday.
Pierre-Emerick Aubameyang opened the scoring from a penalty after Bruno Martins Indi was adjudged to have fouled Mesut Ozil, only for replays to show he won the ball.
Aubameyang added a second before substitute Alexandre Lacazette marked his return from knee surgery with another spot kick.
For sixth-place Arsenal, the priority is wining the Europa League to secure a route back into the Champions League. The north London club hosts CSKA Moscow in the first leg of their Europa League quarter-final on Thursday.
Stoke, which remains next-from-last in the standings, had worked hard and looked to be on for at least a valuable point, until a late capitulation.
The defeat leaves the visitors three points from safety with six games remaining. Stoke had the better of the early exchanges, with Xherdan Shaqiri curling a decent effort wide of David Ospina's post, the Colombian retaining his place in the Arsenal goal as Petr Cech missed out with a groin injury.
Arsenal took some time to get going and did not threaten the Stoke goal until the midway point of the first half.
Hector Bellerin's low cross was deflected up into the air, with Jack Butland only able to send the ball in the direction of Aaron Ramsey, whose looped effort bounced off the top of the crossbar and behind.
It was Ramsey who again came close after some smart work from captain Jack Wilshere allowed him to get a shot away that was deflected off target for a corner.
Mohamed Elneny saw a driven effort blocked by Martins Indi early in the second half, with Nacho Monreal's measured shot from the rebound saved by Butland.
Wenger turned to fit-again Lacazette in the hope of adding to the team's attack, while Stoke introduced Saido Berahino in place of the injured Mame Biram Diouf.
The visitors briefly broke forward with a quarter of the game remaining, Shaqiri only able to angle a shot straight at Ospina following a corner.
The Switzerland international almost scored directly from the next corner, hitting the inside of the post with a whipped set-piece that had Ospina beaten.
Berahino, too, had a decent chance as Stoke looked to spring a surprise, the result of which was a response from the hosts.
Aubameyang, on the periphery for much of the contest, broke the offside trap but was denied by Butland, before Lacazette's close-range strike was blocked behind. Calum Chambers bundled the resulting set-piece into the welcoming grasp of the England goalkeeper.
The turning point came with 15 minutes to go as referee Craig Pawson pointed to the spot after Ozil went down under close attention from Martins Indi. The Stoke defender had a right to feel aggrieved as he got his foot to the ball but Aubameyang stepped up to convert the resulting penalty.
Badou Ndiaye curled an effort wide as Stoke chased a leveler before Butland did well to prevent substitute Henrikh Mkhitaryan and Ozil doubling Arsenal's lead. But Butland could do nothing to stop Aubameyang turning home his second of the afternoon, before Lacazette converted from the spot after he had been shoved over by Ndiaye.