Robin van Persie scored a sensational stoppage-time winner to give Manchester United a 3-2 win at Manchester City yesterday that sent them six points clear in the Premier League.
Pablo Zabaleta looked to have rescued a point for City with an 86th-minute equaliser but in the second minute of injury time, Van Persie's free kick flicked off Samir Nasri and crept in to put United in control of the title race.
Wayne Rooney had put the visitors 2-0 up with a first-half brace, before Yaya Toure replied for City on the hour.
There were unruly scenes in the aftermath of Van Persie's winner, with United centre-back Rio Ferdinand left bleeding after appearing to be struck in the face by an object thrown from the crowd.
Police also arrested a man for alleged racist chanting.
City substitute Carlos Tevez was also fortunate to escape censure for a wild kick at Phil Jones in the dying stages, but the final whistle prompted full-bodied celebrations from Alex Ferguson's visiting players.
"City always come back, we knew that, and it is a really special way to end this game in a dramatic way with the three points," Van Persie said.
"Wazza [Rooney] asked if I was going to shoot or cross from the free kick, and I chose to shoot.
"It was a great atmosphere and everyone was supporting their team. But what you saw happen to Rio should not happen on the football pitch."
Ferguson was delighted. "Today was special because they hadn't lost at home for two years and both of us are contending at the top of the league," he said. "It was a fantastic game and you couldn't take your eyes off it. We should have killed the game off but it's a funny game football, instead of being 3-0 it was 2-1 and it got the fans going." City now find their hold on the title slipping after a week that also saw them eliminated from all European competition.
"We won the league with the last touch of the ball last season," said City coach Roberto Mancini. "This can happen. But we didn't deserve to lose this game. We played very well." Rooney's brace made him the youngest player to reach 150 goals in the Premier League era and took this season's tally to seven in the league - and four in two games.
At Goodison Park, Everton scored two late goals to beat Tottenham 2-1.