Alex Ferguson has confirmed Wayne Rooney will use an oxygen chamber to try to speed up his recovery from a broken foot, even though the club has no idea whether it makes any difference or not.

Rooney is facing an anxious six weeks before learning whether he will be fit enough to go to the World Cup with England, with Sven-Goran Eriksson vowing to take the 20-year-old to Germany if at all possible.

Although he has expressed major doubts over whether Rooney will make it, Ferguson has pledged United will do everything possible to help the striker, with an oxygen chamber at the club's Carrington training complex being the latest development.

"An oxygen chamber will arrive here this afternoon," said Ferguson. "There is no conclusive evidence that it does improve injuries but there is no evidence against it. It won't do any harm and everything is worth a try at this stage."

Ferguson confirmed Rooney suffered two breaks to the same metatarsal when he went over on his foot at Stamford Bridge on Saturday but said confirmation of the second break would have no effect on the player's recovery programme.

"The break he has got in the fourth metatarsal is a small fracture but the one slightly above it is nothing to worry about at all," he said. "It doesn't affect the recovery, there is no damage there at all."

Ferguson stated there would be no deadline placed on Rooney regarding his fitness for the World Cup.

Having reached agreement with Eriksson for the former Everton striker to continue his rehabilitation in Manchester, Ferguson feels Rooney's participation in the World Cup will be determined by further scans later in his recovery programme.

"You can't put a deadline on it," he said. "The scans will tell you everything.

"In a few weeks time we will send him back for another scan. If it has healed then we have the progress we want. If it has not healed, there is nothing you can do about it.

"We will do our very best to get him there. It is in our interests as well as England's to do that. But we want him to do himself justice and we will not jeopardise the boy."