Manchester City beat Manchester United 1-0 at Old Trafford on Sunday, winning the derby despite playing more than 70 minutes with 10 men after Phil Foden's red card.
Erling Haaland scored the only goal, sliding in to convert Josko Gvardiol's deflected cross. The goal was initially ruled offside but was awarded after a lengthy review concluded Enzo Fernandez did not make contact with the ball. United defender Lisandro Martinez called it an "injustice", while Michael Carrick said: "If that's the interpretation of not interfering in the game now, that's really worrying for me. It's a staggering explanation."
Foden was sent off for planting his studs in Bruno Fernandes' midriff, the second red card of his career. City manager Enzo Maresca agreed with the decision but said Fernandes should also have been sent off, adding: "Phil Foden's red card is a red card but I also think it is a red card for Bruno Fernandes."
United struck the woodwork twice, through Marcus Rashford before half-time and Kobbie Mainoo after the break, and had a lone shot on target in the first half. Gianluigi Donnarumma made a 95th-minute save from Bryan Mbeumo. "This wolf in goal giving you so much confidence," said Haaland of Donnarumma. "He is a mad man but he is a match-winner as well."
Maresca said: "To win a game with 10 players is special but it is even more special when it is a Manchester derby." Carrick said: "We had a plan and after the red card it completely changed," adding: "I can't be too critical of the players and I won't be."
The defeat leaves United eight points behind City. It was Maresca's first derby at Old Trafford, following Pep Guardiola's departure.