Wayne Rooney says handing in a transfer request at Manchester United two years ago was the biggest mistake of his career.
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Rooney expressed his desire to leave Old Trafford in October 2010 after questioning the club's ambition and ability to attract top players. The England striker, who was linked with a move to rivals Manchester City, performed a spectacular U-turn just two days later, signing a new five-year deal.
"In September 2010, my ankle puts me on the sidelines," he recalled in an excerpt of his latest autobiography serialised in the Daily Mirror. "I get frustrated with myself, my game, my injury, and everything around me. I'm stuck in a cycle of bad form but I can't get out of it. And that's when I make the biggest mistake of my football career.
"In October, I release a statement which publicly questions my happiness at Old Trafford. Am I better off elsewhere? Everyone makes a fuss. There are discussions inside United to sort out the issue, people outside United chuck their opinions around, but the thing is, nobody really knows what's going on in my life.
"None of them understand where I am in my career. They don't know where my head's at. The only person who really knows what's going on in there is me, but even I'm not sure what I want.''
Rooney, who recently dismissed talk of a last-gasp move before this summer's transfer window closed, revealed Sir Alex Ferguson played a key role in convincing him to stay at the club.
He said: "The manager has his say. 'Sometimes you look in a field and you see a cow and you think it's a better cow than the one you have in your own field. And it never really works that way'.
"He's saying the grass isn't always greener, and he's right. I like what's in my field. I'm wrong. United want the same as me: trophies, success, to be the best."
Meanwhile, Rooney is positive about his recovery from the gash he sustained during the recent victory over Fulham.
He told the Manchester Evening News: "The injury is going well. It could have been a lot worse than what it was. It is up to the doctor. When he declares me fit I will be ready.
"It feels good at the minute. The timescale put on it was four weeks. If that is the time they feel I need for the wound to heal properly then that is what I will do.
"What I don't want to happen is to come back too early when it is not quite healed and it opens up again first game. That would just set me back again another four weeks."
He added: "Overall, I think at the most I will miss four games."