Chelsea's 10 men were stunned by a Zian Flemming header in the third minute of added time as Burnley stole a 1-1 draw at Stamford Bridge.
Joao Pedro's goal in the fourth minute had looked like being the winner but the Blues wilted terribly after Wesley Fofana's sending off for a second booking 20 minutes from the end, leaving the door ajar for Flemming to score from a James Ward-Prowse corner.
Chelsea are much improved since Liam Rosenior took charge but they still look unsure of how to finish off opponents.
The visitors had barely a sniff after Joao Pedro had shovelled Pedro Neto's cross over the line, with Cole Palmer showing some of his very best form as Scott Parker's struggling side were made to look like they were a Championship team already.
Yet Chelsea's issue this season has been ill-discipline, and they were shown an eighth red card of the campaign when Fofana went in late on Ward-Prowse.
Flemming's goal was painful to take and it ought to have been worse, Jacob Bruun Larsen powering a free header over the bar with virtually the final action.
Tammy Abraham netted his first Premier League goal since returning to Aston Villa to rescue a late 1-1 draw against Leeds at Villa Park.
Daniel Farke thought his side had picked up a precious three points to further strengthen their bid to stay in the league but Abraham's late equaliser helped Villa's Champions League hopes.
Leeds had won only once away from Elland Road but they oozed confidence at Villa Park and Anton Stach scored a stunning third free-kick of the season which gave the West Yorkshire outfit a deserved lead on his return to the starting fold following a hip injury.
Karl Darlow made three saves within minutes to keep their lead intact heading into the interval and Ollie Watkins' offside goal came as further frustration to Unai Emery, before Emiliano Martinez's save from Lukas Nmecha kept them in the game.
It looked like Villa would lose a third home game from their last four but they left it late to get on level terms as Abraham bundled in from a corner two minutes from time.
Leeds were denied a first victory away from home since a 3-1 win over Wolves at Molineux on 20 September but did stretch their unbeaten league run to three matches.
Brighton marked James Milner's record-breaking 654th Premier League appearance with a much-needed 2-0 win at Brentford.
The pressure had mounted on Seagulls boss Fabian Hurzeler after a run of one league win in 13 and he again turned to veteran midfielder Milner in attempt to arrest a worrying run of results.
Milner's inclusion meant he moved past Gareth Barry's previous record of 653 appearances in the competition and it proved an occasion to remember all round for Brighton after first-half goals by Diego Gomez and Danny Welbeck.
Gomez scored in the 30th minute to end the visitors' three-match run without a goal and Brentford captain Nathan Collins was at fault when Welbeck made it 2-0.
Collins' poor clearance allowed Welbeck to fire home for his 10th goal this season before Milner's special afternoon concluded in the 90th minute with a round of applause from both sets of supporters at Gtech Community Stadium.
West Ham missed the chance to give their survival hopes a huge shot in the arm after a goalless draw with Bournemouth.
The 18th-placed Hammers could have seriously put the frighteners on the teams above them, as a victory would have put them level on points with Nottingham Forest and two behind Tottenham, both of whom have tough games on Sunday.
But despite dominating for large parts against below-par Bournemouth, they were unable to eke out a goal with captain Jarrod Bowen firing a glorious stoppage-time opportunity over.
Instead, the Cherries left east London having stretched their unbeaten run to seven matches, after the seventh successive draw in this fixture.
However, a point may still prove crucial to West Ham in the grand scheme of the relegation dogfight, especially after Bournemouth winger Rayan clipped the woodwork in the second half.
