Modric celebrates his fine winner as Spurs savour a rare win over Chelsea
Luka Modric capped a man-of-the-match display with a superb goal as Tottenham dealt Chelsea's title bid a huge blow with a deserved win at White Hart Lane.
The Croatian grabbed the winner on 50 minutes, drilling Aaron Lennon's cross into the corner from 18 yards.
It might have been more had Robbie Keane not been denied three times.
But Spurs keeper Heurelho Gomes also played a part, saving brilliantly from John Terry before Alex headed on to the bar as the hosts desperately held on.
The three points were no more than Tottenham deserved from a full-blooded and frantic London derby, but Chelsea will be kicking themselves as their first defeat under Guus Hiddink saw them miss the chance to close the gap on league leaders Manchester United.
United's earlier 2-0 defeat to Fulham meant a win would have taken the Blues to within a point of the champions, but instead they were left to rue a disjointed display and a fine performance from Spurs.
Redknapp ecstatic after win over Chelsea
All signs before the match pointed to a Chelsea victory, given their 100% league record under Hiddink and the fact Spurs had secured just one win in 37 league games against their London rivals.
But Tottenham, unbeaten in five matches themselves, are looking every inch an outfit rejuvenated under Harry Redknapp of late and they edged the opening 45 minutes.
With the Blues deploying a 4-3-3 formation, with Juliano Belletti wide right and Nicolas Anelka wide left, Jonathan Woodgate and Ledley King were able to nullify the threat of Didier Drogba in the centre.
And with Jermaine Jenas and Wilson Palacios impressing in midfield against Frank Lampard, Michael Ballack and Michael Essien, Chelsea's greater possession only rarely led to clear openings.
Essien had the first chance of note, though, playing a one-two with Anelka before unleashing a skiddy shot that Gomes did well to get down and save in the Tottenham goal.
Spurs - and Keane in particular - responded well.
First the Irishman unleashed a fierce half-volley that Petr Cech did well to turn round the post from 20 yards, and the keeper then had to save from two rather tamer efforts from the striker as Tottenham's organised, thoughtful approach play almost bore fruit.
Anelka forced another smart stop from Gomes up the other end with a clipped effort from 16 yards, but it was Tottenham impressing - and they got their reward five minutes into the second half.
Lennon - kept quiet until that point - was the creator, the winger getting the better of Ashley Cole on the right and pulling back to Modric to rifle a superb right-foot shot into the corner from 18 yards.
The goal rattled Chelsea and, buoyed by a vocal home support, Spurs pressed forward.
Modric went close again with a similar effort to the goal and King headed over unmarked from a corner as the visitors backtracked.
Something had to change for Chelsea - and Hiddink obliged by sending on Ricardo Quaresma, with almost immediate affect.
The Portugal winger gained half a yard down the right and his deep cross was headed goalwards by Lampard, only for Vedran Corluka to desperately clear the Spurs lines.
Hiddink regrets missed chance to close gap
Minutes later, Drogba forced a smart near-post save from Gomes, while Keane curled narrowly wide for Spurs up the other end.
It was all set up for a frantic finale - and so it proved, with Drogba heading wide when well placed and Lampard firing wide from close range at one end, and Aaron Lennon wasting a great chance to set up Darren Bent on the counter at the other.
The best chance fell to Terry, though, the Chelsea centre-half rising highest to aim a firm header towards the corner from eight yards out, but Gomes produced a stunning right-hand stop to keep it out and effectively seal the game for the hosts.
There was still time for Alex to head into the ground and onto the bar deep into injury-time, but Chelsea could not find the breakthrough as Spurs held on to jump into the top 10 for the first time this season.
Tottenham manager Harry Redknapp:
"That is a big three points for us and we've been in great form of late, I think that's 18 points from our last nine games, which is terrific.
"We've a long way to go to get into the top four - that's very, very difficult - and I'm not going to kid myself or anyone by saying we're close to that at the moment.
"But we were excellent today and I thought we were comfortable throughout, even if they put us under pressure in the last 10 minutes.
"We're in a good situation now where we can start looking up. I don't know what it'll take to stay up but, with the way we're playing, we're all about how high up we can finish in the table now."
: Gomes, Corluka, Woodgate, King, Assou-Ekotto, Lennon (Zokora 90), Jenas, Palacios, Modric (O'Hara 87), Bent, Keane.
Subs Not Used: Cudicini, Bentley, Huddlestone, Pavlyuchenko, Dawson.
: Palacios, Modric.
: Modric 50.
: Cech, Bosingwa, Alex, Terry, Ashley Cole, Essien (Malouda 76), Ballack, Lampard, Belletti (Quaresma 61), Drogba, Anelka.
Subs Not Used: Hilario, Ivanovic, Di Santo, Kalou, Mancienne.
: Belletti, Ballack.
: Mike Dean (Wirral).
BBC Sport Player Rater man of the match:
Tottenham's Luka Modric 8.37 (on 90 minutes).
Please note that you can still give the players marks out of 10 on BBC Sport's Player Rater after the match has finished.
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