Ferguson said Vidic was back in training despite being forced off inthe 2-1 win over Liverpool at Old Trafford on Sunday.

Vidic collided with Daniel Agger and left the ground on crutches, prompting concerns of an extended period on the sidelines so soon after his return from injury.

However, Ferguson has dispelled those fears, adding that Wayne Rooney and Nani will return for the FA Cup third-round replay against West Ham on Wednesday.

"Actually, Vida's knee is okay," Sir Alex told MUTV. "It was concussion.

"He had a little bit of concussion but he's okay and fine. He trained yesterday and was good.”

The 71-year-old also downplayed suggestions winger Ashley Young faces a spell out after being substituted at half-time against Liverpool with a concern over his knee, although he did reveal that the winger is likely to miss the trip to Tottenham on Sunday.

"There are no other serious knocks really," Ferguson said.

"I think they're all pretty good. Obviously, Young has got a dull knock, a little bit of a strain on the knee, but it's nothing serious.

"I think he'll be back next week. Maybe not for Tottenham but, the week after, he should be okay."