New life has been pumped into the English Premier League title race after leaders Chelsea suffered a shock 2-1 defeat at home to Crystal Palace, enabling Tottenham Hotspur to cut the gap at the top to seven points after their 2-0 win at Burnley.
Liverpool won a feisty Merseyside derby against Everton 3-1 at Anfield to move into third place as Chelsea's pursuers were all given fresh hope after Antonio Conte's side lost their first league match at Stamford Bridge since September.
The unlikely reverse at the hands of Sam Allardyce's resurgent Palace left Chelsea on 69 points with Spurs having moved on to 62 and Liverpool on to 59, though the Reds have played a game more than the top two.
Such has been Chelsea's dominance at the Bridge this season that once Cesc Fabregas had put them ahead after just five minutes, it all promised to be plain sailing towards an 11th straight home win in the league for the Blues.
Yet two splendid goals from Wilfried Zaha and Christian Benteke in the space of three minutes soon after changed the complexion of the game with Palace then defending stoically to earn the unlikeliest of wins.
Spurs had appeared to be labouring at Turf Moor without injured striker Harry Kane and they lost Victor Wanyama and Harry Winks -- the latter to what appeared a serious ankle injury -- before the interval.
Yet Eric Dier and Son Heung-min struck in the second half to earn the points.
With Chelsea on Wednesday next facing Manchester City, who currently lie fourth on 57 points and who first face Arsenal on Sunday, the Blues' defeat gives a markedly different feel to the title race.
Juergen Klopp became the first Liverpool manager to win his first three Merseyside derbies as his side enhanced their top-four push with an important triumph with goals from Sadio Mane, the inspired Philippe Coutinho and Divock Origi.
Liverpool made it 17 league matches unbeaten at Anfield against their city rivals after Mane's brilliant early individual effort was answered by a first goal for Everton from Matthew Pennington.
The youngster, though, was bamboozled less than three minutes later by the skill of Coutinho, who curled a delightful shot into the corner before sealing his masterful display by putting in substitute Origi.
There was off-pitch drama as Everton boss Ronald Koeman criticised Klopp and the Liverpool bench for their behaviour after the home contingent were left enraged by a bad tackle from Ross Barkley on Dejan Lovren.
"Tackles are part of football...we don't make a show from the bench like Liverpool," Koeman told Sky Sports.
"I don't like coaches from the bench the whole time shouting to referees and linesmen, making a big show about tackles.
"They were crazy, they didn't need the physio on the pitch. It's a man's sport."
Manchester United slipped again in the race for Champions League places, being held to a goalless draw at Old Trafford by West Bromwich Albion, which leaves Jose Mourinho's team in fifth place on 53 points.
At the other end of the table, Sunderland's plight is looking increasingly dire following another defeat, with Miguel Britos heading home the winner in Watford's 1-0 win at Vicarage Road.
The Black Cats' misery was further compounded when they heard Hull City had come from behind to beat West Ham United 2-1 with Andrea Ranocchia notching the Tigers' 85th-minute clincher.
It meant Sunderland were stuck on 20 points while 18th-placed Hull moved on to 27 points.
Craig Shakespeare's extraordinary start to management at Leicester City continued as the champions beat Stoke City 2-0 with goals from Wilfred Ndidi -- a quite superb strike -- and Jamie Vardy.
Victory meant that Shakespeare has become the first British manager ever to win his first four top-flight league games in the Premier League era.
Southampton and Bournemouth drew nil-all.