Ferguson described England coach Sven Goran Eriksson's hopes that Rooney would have recovered from a broken metatarsal bone in his right foot in time to feature in the latter stages of the tournament as "a wild dream."

The Scot's sceptical blast poured icy water all over Eriksson's optimistic plan to name Rooney in the squad he will announce on May 15, even if he is certain not be fit for England's World Cup opener against Paraguay on June 10.

"We have to make sure we don't build up people's expectations which is what's happening at the moment," Ferguson said, voicing scepticism about the chances of Rooney, who suffered the injury on Saturday, being anywhere near ready to play again by the time the World Cup kicks off.

"Sven is going on saying he will take the lad in six weeks and then he will have two weeks to play in the quarterfinals of the World Cup. That is a wild dream.

"It's important Wayne gets a good recovery time. It's folly to say Wayne could be out there in six weeks and then play in the World Cup quarterfinals. If Wayne's not ready he's not going to go."

Ferguson had earlier insisted that he would do everything he could to help England's medical staff get Rooney ready in time to play some role in the tournament.

The United boss also acknowledged that Rooney would be personally distraught at missing out after suffering an almost identical injury to the one that ended his involvement in Euro 2004, the tournament at which he announced himself to the world as a precociously talented 18-year-old.

"This time round it's even worse because he's more mature and is a more rounded player who has improved dramatically over the last two years," Ferguson said. "So it's a real, real blow."

The only consolation for Ferguson was that the striker would be relieved of the burden of carrying all England's hopes in Germany.

"I said a few weeks ago I didn't want to see this kind of pressure on a lad of 20 years of age," he said. "Other more experienced players such as David Beckham, Steven Gerrard, Frank Lampard, John Terry, Rio Ferdinand and Gary Neville, should be taking the mantle.

"If England don't have Wayne Rooney they will need to look at getting inspiration from other players."