The five-times Olympic champion was 200 kilometres from the end of the 3,000km coast-to-coast journey over the Rockies and Appalachian mountain ranges when he lost control of his bike after a tyre punctured on a downhill corner.

"If I had been on a straight bit of road I would have had more chance of keeping control," said Redgrave, who, at the age of 48, was riding with seven old rowing pals to raise a further £100,000 for The Steve Redgrave Fund and Sport Relief.

A spokeperson for Redgrave added: "The rest of the team have completed the ride and met up with Steve.

"Because his feet were attached to the pedals there was nowhere for him to go when the crash happened.

"He has been released from hospital, but he had concussion as well, and there may be some delay before he can fly back home.

"When he gets back to England he is going to need another operation to put a plate into his cheekbone."

Redgrave’s accident may also affect his participation in this summer’s Henley Royal Regatta which runs from June 30-July 4, where he would normally be fulfilling his duty as one of the events 57 stewards.

"Last year he turned up to Henley with a leg in plaster after breaking it during a fall while playing golf,” the spokesperson said.

"It looks like he will be in the wars again for this year’s event if he goes.

"But we don’t know yet when he will have his operation."

Despite Redgrave’s failure to complete the course, his team mates still reached the end of the course within the time-frame of eight days, and the amount raised will mean that Redgrave’s fund, which has raised close to £6 million ($9 million) since being set up in 2001, will be able to extend its Inner City Rowing Scheme to another city.

"We’ve already set up these schemes, and other community support, in deprived areas in Birmingham, Sandwell, Glasgow, Cardiff, Rochdale and Southampton," he said before setting off.

"We will announce another opening in September, and this ride will mean we can do one after that.

Redgrave had been rueful about his latest challenge.

"I tend to be more of a sprinter, more of an explosive athlete,” he said.

"I would much rather race Sir Chris Hoy round a track than cycle across America."

Doubtless he will be even more strongly of that opinion now.

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