Sir Alex Ferguson has responded to Owen Hargreaves's claims that Manchester United doctors used the midfielder as a "guinea pig".

Hargreaves, who joined Manchester City this summer, was plagued by injury problems during his time with the Red Devils. He suffered from tendinitis in the 2008/9 season and underwent double knee surgery followed by further treatment which, he has claimed, hindered his recovery.

"I've had to be a guinea pig for a lot of these treatments," the 30-year-old said. "But when you're left to try to make something of a difficult situation, it's not really an option to say, 'Let's sit it out and rest for six months.'"

However, United manager Ferguson has today stressed his confidence in his medical team.

"We're trying to analyse all the stuff he has said and there will be a statement later to address that," he explained.

"As far as I am concerned my medical staff is one of the main reasons why we have been so successful over the last few years. Do you think we would be successful if they were not 100% brilliant? Our doctor and his five physios are fantastic.

"That's my opinion of Manchester United and that's more important than what anyone else has got to stay about that."

Manchester United will travel to face Stoke City for tomorrow's Premier League meeting.