Manchester United manager Alex Ferguson says he doubts whether David Beckham's arrival in the US will spark a surge of interest in football there.
Ferguson, who sold Beckham to Spain's Real Madrid in 2003, said the likes of Franz Beckenbauer, Pele and Johan Cruyff had all gone to play in the US but had failed to raise the profile of the sport.
"It is difficult with David going there," Ferguson was quoted as saying in the Times.
"I don't know what kind of impact he can make. David Beckham himself can't change the whole country."
Former England captain Beckham left Real Madrid at the end of last season to join MLS outfit Los Angeles Galaxy. His arrival created a wave of media interest but he is currently sidelined with a knee injury.
Beckham, who signed a lucrative five-year deal with Galaxy worth up to 128 million pounds, said he wanted to raise the level of the MLS, but Ferguson is sceptical.
"The size of the country makes it difficult," Ferguson said. "In European football you can travel easily. If you're in Boston and need to go to Los Angeles it's a six-hour flight.
"Supporters don't travel so you miss that rivalry so you have a problem.
"To make it substantial you would have to go regional but there are not enough teams to have four strong leagues."
Of his own future, Ferguson said he had no plans to retire but that his assistant Carlos Queiroz would be a good choice to replace him when he decides to call time on his career.
"I have a great assistant in Carlos and I think he will be a strong candidate. We have new owners now and I don't know how they will look at the situation in America."
United were bought by the Glazer family and Ferguson said he was happy with their input.
"They have been great supporters of everything we have done, but they may have their own ideas. The thing is I've not made up my mind when I'm retiring. It's a difficult one.
"The important thing is to leave a good team. The present team is very good, but they will get better."