Manchester City players surrounded the officials in the Old Trafford tunnel following their controversial derby defeat to Manchester United, sources have told ESPN.

City were left furious after Bruno Fernandes' equaliser was allowed to stand despite Marcus Rashford straying into an offside position.

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The goal was initially ruled out by the linesman but was then awarded by referee Stuart Attwell because Rashford did not touch the ball before Fernandes scored.

Pep Guardiola argued afterwards that the forward had interfered with play before the goal, which came just four minutes before Rashford scored to seal United's 2-1 win.

The controversy led to an angry confrontation between players and officials in the tunnel after the final whistle. Jack Grealish, who opened the scoring for City, was seen remonstrating with Attwell as they left the pitch and the arguments continued on the way to the dressing rooms.

"To be honest, the first goal is a joke that it's allowed. Rashford is clearly offside so I played him offside," City defender Manuel Akanji said. "He runs to the last second and only stops because Bruno is coming in behind him.

"I understand he doesn't touch the ball but he runs for 30 metres, chasing the ball then he stops. The ref didn't look at the situation.

"The referee didn't say anything to me but I talked to the linesman and he said, 'Did Rashford touch the ball?' I said, 'no but he's chasing the ball for a long time.'

"In that situation, the referee has to at least look at the situation and can understand the situation I am in and Kyle [Walker] on the other side.

"Probably the pressure got to him in the stadium. That's why he decided to let it go."

Akanji also hinted at the confrontation in the tunnel after the City players and the officials, including Attwell, assistant referees Gary Beswick and Darren Cann as well as fourth official Robert Jones, left the pitch.

"I came really late to it," he said. "When I was there it was close to the end. I don't know how it started or what was the actual reason but everybody was not in a good mood."