Manchester United defender Rio Ferdinand has been struck with a missile thought to have been thrown from the crowd as his team's derby clash with Manchester City ended in ugly scenes.
Ferdinand was seen wiping blood from his face following the incident which took place in the aftermath of United's injury-time winning goal in their 3-2 victory at the Etihad Stadium. City trailed 2-0 but fought back to equalise before Robin van Persie's late free-kick secured three points for their arch-rivals.
A message on Ferdinand's official Twitter account posted at 4.34pm read: "what a result,3points! Sweet! Whoever threw that coin,what a shot! Can't believe it was a copper 2p....could have at least been a £1 coin!"
Praising the football, United manager Sir Alex Ferguson told Sky Sports: "It's just unfortunate towards the end a City fan runs on and then they throw coins at our players and that. I don't think you need that.
"The same thing happened at Chelsea which was masked really by all the other things that happened. But, you know, two fantastic teams today I think, and a fantastic game of football, and it could do without that."
According to Greater Manchester Police's (GMP) Twitter feed, there had only been one arrest by 2pm of a suspected ticket tout outside the stadium. During the game GMP said a man was arrested inside the ground on suspicion of committing a racially aggravated public order offence after officers heard racist chanting.
After Ferdinand was struck by the missile, a Manchester City fan ran on to the pitch in the England defender's direction. He slipped and fell to the ground as he approached the player up to 10 yards away and was then obstructed by City keeper Joe Hart who pushed him away.
On his Twitter account, Ferdinand added: "Respect to Joe Hart for protecting that idiot who ran on!! Love the banter between fans but there is a point when it goes too far...calm it!" His team-mate Ashley Young told MUTV: "It could have taken Rio's eye out and you've seen the cut on his head."
In a statement, Manchester City said: "Manchester City FC security officials are co-operating fully with Greater Manchester Police in relation to events leading up to the throwing of missiles onto the field of play, and between the two sets of supporters, during today's game against Manchester United.
"Manchester City wishes to offer its sincere apologies to Rio Ferdinand. The club unreservedly condemns the actions which led to his being injured." The Football Association (FA) confirmed it was investigating the Ferdinand incident.