Ten-man Leicester produced an outstanding display to earn a point at third-placed Chelsea - although they should probably have come away from Stamford Bridge with all three.
The Foxes dominated possession for large periods and created the better chances but had the sting taken out of their display when defender Ben Chilwell received two yellow cards in the space of five second-half minutes. He was shown no mercy by referee Mike Jones in the 68th minute when he brought down Victor Moses, shortly after fouling Willian.
Claude Puel's side went close twice through Jamie Vardy, while Wilfred Ndidi's header was acrobatically pushed away by Thibaut Courtois.
Chelsea looked leggy and short of ideas. Cesc Fabregas had two good efforts - twice testing Kasper Schmeichel - and seconds from the end the Danish keeper pushed away a free-kick from Marcos Alonso.
The Blues are now level on points with second-placed Manchester United, who play on Monday.
Leicester have 31 points and remain in eighth.
Foxes' good work undone by Chilwell red
It was the generally more timid of the two managers who got their side to play the more exhilarating football at Stamford Bridge.
Puel's side harried the Blues from the first whistle, and should have scored at least once from one of their three chances in the 10th minute.
England striker Vardy, fit again after a groin problem, found the side-netting and fired just wide, while Shinji Okazaki also missed narrowly after more initial good work by Vardy.
Riyad Mahrez has been the subject of rumours linking him to Liverpool and Arsenal, but today his mind was clearly on the matter in hand. He was exceptional in midfield and found Vardy twice with two exquisite passes, only for the striker to miss the target with one strike and see another blocked by Gary Cahill.
The Foxes looked set to turn the screw midway through the second half, but had to change their gameplan when England Under-21 defender Chilwell was sent off for a second bookable offence.
Nevertheless, the defence continued to look comfortable against a Chelsea attack bereft of ideas. The only time Schmeichel was severely tested was moments before the final whistle when he tipped Alonso's low free-kick around the post.
Tired-looking Blues deliver lacklustre performance
Did fatigue play a part in Chelsea's dispirited display? Or did manager Antonio Conte's suggestion he might not be at Stamford Bridge next season have anything to do with it?
This was Chelsea's seventh game in 21 days and they looked like a side sapped of energy.
Striker Alvaro Morata, who had a great first half to the season with 13 goals from 26 matches in all competitions, has not found the net in his past five and did not have one effort against the Foxes.
Wing-backs Marcos Alonso and Victor Moses barely troubled the opposition full-backs, while playmakers Fabregas and Eden Hazard were both replaced only 13 minutes into the second half.
Bar two good saves to deny Fabregas, there was no need for heroics from Schmeichel until the final seconds when he kept Alonso out.
This looked an excellent chance for Chelsea to regain second place. Now Conte's side have to pick themselves up for another four games in 14 days.