Amad Diallo has scored a 90th-minute winner as Manchester United staged a stunning late comeback to beat Manchester City 2-1 in the Premier League.

Four-time defending champions City had led the derby 1-0 going into the 88th minute at Etihad Stadium on Sunday, thanks to Josko Gvardiol's headed goal in the 36th.

But Bruno Fernandes levelled the game from the penalty spot before Diallo flicked the ball past Ederson to score the winner for United.

City fans jeered at the final whistle as their once dominant team's woeful run of form extended to one win and eight losses in 11 games.

It was a first derby victory for new United head coach Ruben Amorim, who led Sporting Lisbon to a 4-1 win against City in one of his last games in charge of the Portuguese club in November.

"I think we did a great job, we controlled it very well," Amorim said.

"We didn't allow much, of course we don't create so much either but it was a divided game. But we believed a lot.

"I think for the fans it has a deep meaning ... but we had a difficult moment one week ago against Nottingham (Forest) at home, in the storm.

"Today is a good day, let's enjoy it for 10 minutes and then think about the next game."

United are now 13th and five points behind fifth-placed City (27 points).

Chelsea won their fourth league game in a row, beating Brentford 2-1 at Stamford Bridge.

Goals by Marc Cucurella and Nicolas Jackson either side of halftime leaves the Blues two points behind leaders Liverpool (36), having played one more game.

Bryan Mbeumo pulled on back in the 90th minute for the Bees, who drop to 11th.

Tottenham eased pressure on manager Ange Postecoglou with a thumping 5-0 home win against bottom-of-the-table Southampton on the south coast.

The former Socceroos boss saw his side score all their goals in a scintillating first half, with Son Heung-Min, Dejan Kulusevski and Pape Matar Sarr on the scoresheet in between a James Maddison double to lift Spurs up to 10th.

Elsewhere, Ismaila Sarr netted twice as Crystal Palace beat Brighton & Hove Albion 3-1.

The forward also provided an assist for Trevoh Chalobah in the win at Amex Stadium, which lifted Palace four points clear of the relegation zone.

Brighton are now ninth and without a win in four matches.

With PA & AAP.