The Northern Ireland international revealed last summer that he feared he could be forced to leave Old Trafford unless his displays improved.
“Maybe I was too honest and shouldn’t have said that,” he told the club’s official website. “But that was an honest opinion of myself, I guess.
“Every player goes through that. It was up to me to find a way to get through it. It was a challenge for me and everybody needs to be challenged.
“You either rise to it or you don’t, and if you don’t then you don’t deserve to be at a club like Manchester United.
“Those are the sorts of challenges everybody here faces – when that happens it’s up to you to try and raise your game and get back into the team.”
“When I came back from being on loan at Sunderland [in 2007/08] I never thought I’d go on to play more than 30 games in my first season at United. That was crazy,” he continued.
“And I don’t think about how many games I might end up playing. My aim is always to just get into the next team and then play well.
“I’ve been here about four years and I’ve played 120-odd games – that’s about 30 a season. Hopefully I can add a few more to that next year.”