The popular, cigar-chomping Northern Irishman, whose wife, Heather, lost her battle with cancer only six weeks before he played a starring role in Europe's Ryder Cup victory, had been quoted at odds of 2/5 to win the coveted prize.

But the bookmaker William Hill acted after Eamonn Holmes said on his Radio 5 Live show on Saturday that he had heard Clarke was to rule himself out of the competition.

It is thought Clarke is thought to be reluctant to have his personal grief put under the spotlight again by appearing on television.

He said only decided to compete in the Ryder Cup because he felt it was what his wife would have wanted.

William Hill feared his rumoured withdrawal would prompt a rush of money on other hopefuls, such as Andy Murray and Zara Phillips, leaving it facing heavy losses.

A spokesman for William Hill said: "Darren had been a very hot favourite with us and that is shown by the money that punters have had on him.

"Any bets already placed on Darren will stand, but from now on, we are betting without him until and unless the situation is resolved for sure one way or the other."

The spokesman went on: "If it's right he has withdrawn, it will be unprecedented in the history of the show, but it goes to show the man's character.

"He is loved by the public, who have shown tremendous warmth towards him after all he has been through this year. I'm sure that, although he may pick up the Team of the Year award, he would rather win the big prize after winning a major."

According to the Hill's spokesman, the rumours that Clarke would pull out of the running for the BBC award started as soon as the European side beat the United States at the K Club in County Kildare, Ireland, last month.

He said: "We have to react to these rumours quickly or we might find ourselves in a position where we take a financial hit."

No further wagers on Clarke would be accepted - unless the golfer confirmed he would be prepared to accept the award.

No-one from Clarke's management company, ISM, was available for comment last night. But a spokeswoman for the BBC said that, as far as the corporation was concerned, Clarke was still a contender for Sports Personality.

She went on: "We are aware of the 5 Live programme. However, we haven't been told that Darren is pulling out, so we can't confirm it. Until we hear otherwise, he will continue to be in the running."

Clarke, 38, became a sporting hero after he agreed to play in the Ryder Cup despite having lost his wife so recently.

His outstanding performance helped seal Europe's third successive victory and he fought back the tears as Ian Woosnam, the team captain, hugged him at the end. The team wore pink blazers, the symbol of the breast cancer, for the awards ceremony, in honour of Heather.

Zara Phillips is now odds-on favourite to follow in her mother's footsteps

ZARA Phillips, has taken over as favourite, at 8/11, to win the BBC Sports Personality of the Year award after William Hill suspended bets on golfer Darren Clarke.

Phillips, 25, became the first Briton to win the World Equestrian Championships in 25 years when she took gold in Germany in August. Her mother, the Princess Royal, an Olympic-standard rider, won the BBC award in 1971.

The Welsh boxer Joe Calzaghe, the world super middleweight champion, is second favourite at 7/2. But he may have dented his chances when he said he didn't expect to win - because Britain prefers losers to winners.

The performances of Scottish tennis sensation Andy Murray, 19, including a straight-sets victory in the United States over the world No 1 Roger Federer, have put him at 8/1 to win.

The spin bowler Monty Panesar, 24, the hero of England's win over Pakistan in August, is at 10/1.

The golfer Paul Casey stands at 14/1, ahead of three people on 16/1 - the Welsh cyclist Nicole Cooke, 23, who won the women's Tour de France, England's Ashes hero Andrew Flintoff and the comedian David Walliams, who swam the English Channel this year.

Further down the betting are the boxer Ricky Hatton, the Liverpool footballer Steven Gerrard and cricketers Steve Harmison and Kevin Pietersen