The 31-year-old, signed for £30 million in 2008, has found himself on the fringes this season but is still focused on doing what he can to help the champions retain the title
The 31-year-old has only made 10 appearances in the Premier League so far this season, with half of those coming as a substitute. He has also played three times in both the Champions League and League Cup respectively.
The Bulgarian suggested that it is hard to take when he doesn't play but insisted that having a strong squad is important.
He told the United Review: "It's just about being ready.
"We have a big squad and you know sometimes you are not going to play.
"It's sad and it's painful but you need to be strong and be prepared for when your team-mates need your help. We are a team and we want to win together.''
In the 10 league games he has featured in, the forward has netted an impressive seven goals. The former Tottenham man believes he has shown Sir Alex Ferguson what he can do and it is just a case of waiting for his chance to help the side regain the Premier League trophy.
He added: "Every time I have played I think I have done well.
"I'm ready and waiting whenever the boss gives me a chance to show my quality and deliver. I want to do as much as I can to help us win the title.''
United are currently two points behind Manchester City, who sit at the top of the table, with the Red Devils set to face West Brom at Old Trafford on Sunday.
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