Amad Diallo inspired a remarkable late turnaround as Manchester United came from behind to seal a dramatic 2-1 derby victory over Manchester City at the Etihad Stadium.

Out-of-form City looked set to move within six points of Premier League leaders Liverpool after Josko Gvardiol's header put them in the ascendency in the first half.

Kevin De Bruyne played a one-two with Ilkay Gundogan from a corner, with his deflected cross being powered home by Gvardiol at the far post.

However, Pep Guardiola's side were far from their best throughout Sunday's contest and were hit with two late sucker punches, with Diallo playing a central role in both goals.

The 22-year-old seized upon a dreadful back pass from Matheus Nunes before being fouled by the Portugal international for an 88th-minute penalty, which Bruno Fernandes converted to wipe out City's lead.

Diallo then darted onto Lisandro Martinez's long ball forward with stoppage time looming, beating Ederson with an excellent first touch before tucking home the winner from a tight angle.

Following a statement win for their new boss Ruben Amorim, United climbed to 12th and are now just five points adrift of City, who remain fifth, nine points off the top.

Data Debrief: The Diallo derby

Diallo wrote his name into United folklore with a dramatic winner in an FA Cup quarter-final victory over Liverpool last season, as the Red Devils went all the way in that competition under former boss Erik ten Hag.

On Sunday, he reaffirmed his status as United's newest hero by scoring just the seventh 90th-minute winner against a reigning champion, and the second by a United player. Robin van Persie netted the other, also against City, back in December 2012.

City, meanwhile, were beaten having been ahead in the 88th minute – the latest point at which a reigning Premier League champion has ever led in the competition when going on to lose.