Owen Hargreaves has criticised former club United over the way they managed his fitness [GALLO/GETTY] 

Manchester United manager Alex Ferguson defended his club's medical staff on Friday after Owen Hargreaves accused the Premier League champions of treating him like a "guinea pig" during an injury-hit spell with them.

Hargreaves, who joined rivals Manchester City as a free agent in the close season after four years in the red half of the city where he made just 39 appearances, said injections he had received had hampered his recovery from knee problems.

"We've been trying to analyse all the stuff he's said this morning and we are going to have a club statement to address that," Ferguson told a news conference.

"But as far as I'm concerned...my medical staff are one of the main reasons Manchester United have been so successful in the last few years. There is absolutely no doubt about that. We have fantastic medical staff and great sports scientists.

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

Canadian-born Hargreaves, whose career has been blighted by chronic tendinitis in his knees requiring surgery, was critical of his former club in comments reported by local media but was urged by current boss Roberto Mancini not to dwell on the past.

"I received some injections and my tendon was never the same," said Hargreaves, who moved to United from Bayern Munich in 2007 despite having broken his leg.

"I tried to get back on my feet and (United's medical staff) said my tendon was good, but it felt like I was made of glass.

"(The injections) obviously had a huge impact. With hindsight, I probably should not have had them. It's difficult.

"I've had to be a guinea pig for a lot of treatments."

Hargreaves, 30, made his first appearance for his new club this week, marking the occasion with a stunning goal in the 2-0 victory over Birmingham City in the League Cup.

While Hargreaves is not convinced by the medical support at Manchester United, striker Javier Hernandez is likely to have little complaints as he returns to action this weekend.

        Hernandez suffered a vicious challenge by Cole during clash with Chelsea [GALLO/GETTY] 

Hernandez is in line for a surprise return when the Premier League leaders visit Stoke City on Saturday, manager Alex Ferguson said.

The Mexican goal-poacher had been facing two weeks out with a bruised shin after what Ferguson branded a "shocking" tackle by Chelsea defender Ashley Cole in last Sunday's 3-1 win over the London side.

"It's quite surprising, Hernandez trained yesterday," Ferguson told a news conference on Friday.

"He is very lucky. At the time he had no feeling in the leg, there was a numbness there, we thought there may have been some nerve damage... but he's trained very well and he's available for tomorrow."

Hernandez is likely to resume his potent partnership with Wayne Rooney, who has scored in all five of United's league games and notched nine goals including two hat-tricks.

United are the only team still with a 100 percent record in the league, topping the table with 15 points. They are two points ahead of neighbours Manchester City and a further three ahead of Chelsea.

Source: Agencies