Harry Kane's double gave Tottenham Hotspur a shock 3-2 win away at leaders Manchester City after Liverpool came from a goal down to beat Norwich City 3-1 on what could prove to be a pivotal day in the Premier League title race on Saturday.
City seemed to have salvaged a point when Riyad Mahrez fired home a penalty in stoppage time at the Etihad, but Kane capped a superb display to head home a dramatic winner three minutes later.
Chasers Liverpool had earlier been give a fright when they trailed struggling Norwich midway through the second half at Anfield. But goals by Sadio Mane, Mohamed Salah and Luis Diaz allowed Juergen Klopp's side to close the gap to six points at the top, and they also have a game in hand over City.
With 14 wins from their last 15 games and facing a Tottenham side on a three-match losing streak, City were expected to regain their nine-point advantage. But Antonio Conte's side had other ideas and claimed a league double over the champions.
"Sometimes you have these kind of games and you need to learn from it. It's a wake-up call for us. There's still a long way to go," City captain Ilkay Gundogan said.
A week after becoming world club champions third-placed Chelsea got back to domestic duty with a 1-0 victory at Crystal Palace, with Hakim Ziyech scoring late on.
In the race for a top-four finish, West Ham United faltered in a 1-1 home draw with resurgent Newcastle United, a result that prevented them moving back above fourth-placed Manchester United, who are in action against Leeds United on Sunday.
United have 43 points from 25 games, one more than West Ham and Arsenal who beat Brentford 2-1. Arsenal have three games in hand compared with West Ham and two over United.
Tottenham moved back into seventh spot with 39 points and also have games in hand over West Ham and United.
It was a big day at the bottom as well with Burnley moving off the foot of the table with a 3-0 win at Brighton and Hove Albion, new signing Wout Weghorst scoring one and creating another.
Watford earned a first win under new manager Roy Hodgson, Emmanuel Dennis securing the 1-0 victory at Aston Villa.
Norwich are now bottom on goal difference behind Burnley with both on 17 points, although Burnley have three games in hand. Watford are a point better off, four points behind Newcastle, for whom Joe Willock grabbed the equaliser at West Ham.
Frank Lampard's Everton lost 2-0 at Southampton and are only four points above the relegation zone.
Kane had appeared close to moving to City in the summer, and how the champions might wish they had sealed the deal.
It was his pass that sent away Son Heung-min in the fourth minute to roll the ball in to Dejan Kulusevski to slot home.
Gundogan capitalised on a fumble by Hugo Lloris to equalise before halftime, but Kane produced a silky 59th-minute finish from Son's pass to restore Tottenham's lead.
It was the 36th time the two had combined for a Premier League goal, equalling the record of former Chelsea players Frank Lampard and Didier Drogba.
Kane had another goal ruled out for offside before a handball by Cristian Romero in the 90th minute allowed Mahrez the chance to equalise from the spot.
But Kulusevski then set up a late headed winner from Kane, opening the door for Liverpool in the title race.
With a game in hand and a trip to City in April, Juergen Klopp's side are now serious contenders again having fallen 12 points behind in January.
They were made to work hard by battling Norwich, but they eventually made sure of their eighth successive win in all competitions, with Salah scoring his 150th goal for the club and Diaz his first.
Joel Matip had deflected in Milot Rashica's shot to give Norwich the lead, but the visitors could not hold back the red tide as Liverpool cranked up the pressure on them - and on City.