Erling Haaland scored the winner for Manchester City at Old Trafford. Alex Livesey - Danehouse/Getty Images
Manchester City continued their perfect start under Enzo Maresca after hard-fought 1-0 win over Manchester United in a match that was fraught with incident.
It was a derby shaped by two contentious VAR decisions. The first of which saw Phil Foden sent off early in the first half for kicking out at Bruno Fernandes and the second that saw Erling Haaland's goal stand despite appearing to be in an offside position.
Foden's return to City's starting lineup after being benched against Coventry last week proved shortlived after he was shown a straight red card in the 22nd minute. The England international's outstretched leg made contact with Fernandes' stomach and despite his protests, VAR ratified his sending off.
Despite being a man down, City played with confidence and didn't relent in their intensity. United struck the woodwork either side of the break through Marcus Rashford and Kobbie Mainoo, but were largely kept at bay by a disciplined City rearguard.
As is so often the case, the breakthrough for City came at the hour-mark through Erling Haaland after he expertly finished at the far post from a Josko Gvardiol cross. The goal was initially ruled out for offside but after a lengthy VAR check, the decision was overturned.
Patrick Dorgu appeared to play Haaland onside but the debate will rage over whether Enzo Fernandez was interfering with play from an offside position right in front of goal befor the ball reached Haaland.
United continued to press hard for a way back, bringing Benjamin Sesko off the bench for the closing stages. Bryan Mbuemo drew a sensational save from Gianluigi Donnarumma in injury time as City held on for a hard-fought win.
Should Phil Foden have been sent off?
The game's first inflection point came in the 22nd minute after Phil Foden became the first Manchester City player since 2006 to be sent off in the derby.
The England international kicked out at Bruno Fernandes' stomach after a coming-together between the two near the touchline. Referee Michael Oliver's decision to brandish a red card was backed up by VAR, howeve,r Fernandes went unpunished.
The last player to receive a red card in the Manchester derby was Marouanne Fellaini back in April 2017, after he blatantly headbutted Sergio Aguero. This one, however, divided opinion.
Phil Foden was sent off in the first half. Carl Recine/Getty Images
While Foden did flick his foot up at Fernandes' midriff, he made only slight contact and appeared stunned to receive his marching orders. It was a sentiment reflected by former Man United midfielder Roy Keane in the Sky Sports studio.
"Foden does react. The strange thing is that Fernandes gives a kick ... for me, he is the one who is violent here," Keane said.
"I don't think it's a red card for Foden, l really don't."
Ultimately, once Foden angrily reacted and his foot made contact with Fernandes, he left the referee with no option but to send him off.