Sir Steve Redgrave quits Devizes to London canoe race
Olympic rowing legend Sir Steve Redgrave has pulled out of the annual Devizes to Westminster canoe race due to "tiredness".
A race spokesman said the Olympian and his partner Roger Hatfield had "retired" from the race at 02:20 BST.
The pair had travelled about 87 miles (140km) along the 125-mile (200km) route, reaching Old Windsor Lock in Berkshire.
The race is considered to be one of the world's toughest endurance challenges.
It begins in Devizes, Wiltshire, on the Kennet and Avon Canal and traditionally takes place over the Easter weekend.
Sir Steve was one of four Olympians taking part in the race, including Ben Hunt-Davis, Sarah Winckless and Kate MacKenzie, all of whom failed to finish.
Mr Hutchison added that about a third of those who took on the challenge failed to complete it.
Sir Steve, 50, who won gold medals at five consecutive Olympic Games, said just before setting off that he was not "looking forward" to it.
"It's a funny sort of race. I'm used to quick blasts of 2,000 metres," he said.
"I've enjoyed the training but I'm not looking forward to the race."
Sir Steve, who only took up canoeing last year, said the furthest he had paddled before was 55 miles (88km).
Prior to retiring from the race he had been expected to reach Westminster Bridge at about 07:00 BST.
There are five classes in the event including a non-stop version of the race, which is the longest non-stop canoe race in the world.
The first 52 miles are along the Kennet and Avon Canal and the next 55 miles are on the River Thames. The canoeists pass through 77 locks.
The current record time for completing the race is 15 hours and 34 minutes, set in 1979 by Tim Cornish and Brian Greenham.
The race ends at Westminster Bridge near the Houses of Parliament.
The event was won by Richard Hendron and James King for the third year in a row.