David Beckham faces an almost insurmountable job to turn football into one of the USA's major sports, according to Sir Alex Ferguson. The Manchester United manager feels that his former protege cannot transform the fortunes of the sport by himself, saying the sheer size of the USA stunts the growth of Major League Soccer despite Beckham's best efforts.

"The size of the country makes it difficult," he said. "In European football, and especially in British football, you can travel easily. If you are Boston and need to go to Los Angeles it's a six-hour flight. Supporters don't travel so you are missing that rivalry between fans.

"So you have a problem. To make it substantial you would have to go regional but there's not enough teams to have four strong leagues."

Ferguson also claimed the former Real Madrid player's celebrity status had overshadowed his significance as a footballer.

"He was never a problem until he got married," Ferguson said. "He used to go into work with the academy coaches at night time, he was a fantastic young lad. Getting married into that entertainment scene was a difficult thing - from that moment his life was never going to be the same.

"He is such a big celebrity, football is only a small part. The big part is his persona."

Los Angeles Galaxy signed Beckham - currently out with a knee injury - on a five-year contract worth up to £128million in a bid to boost the popularity of the game in America. But Ferguson feels the England midfielder will struggle to have a major impact on his own when the combined talents of Pele, Johan Cruyff and Franz Beckenbauer failed to have a lasting impact after playing for New York Cosmos three decades ago.

"In the late Seventies I went to America with Aberdeen and there were guys like [Teofilo] Cubillas and [Peter] Shilton there," Ferguson said. "Before that there was Pele, Cruyff, Beckenbauer. It is difficult with David going there - I don't know what kind of impact he can make. David Beckham himself can't change the whole country."

Ferguson also feels the MLS is also undermined by an exodus of young homegrown talent.

"What you have got in the States is that a lot of kids are playing football in the States and there is nowhere to go," he said. "The best American players go to Europe very early, like Brad Friedel [at Blackburn], [Brian] McBride and [Clint] Dempsey at Fulham. So that situation doesn't help the American game."

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