USAIN BOLT'S coach is worried that going for the sprint double in the Beijing Olympics could hurt the 100-metre world record holder's chances of winning his preferred 200 race.

The Jamaican sprinter has said he wants to compete in both, but is leaving the final decision to coach Glen Mills.

"You have to ensure that you are not going into it just because there is a chance of glory, you have to go there knowing that your chance is solid," Mills said after Bolt's 200 victory yesterday at the London Grand Prix. "I think he will get a medal in both, it's a question of winning."

Bolt's 19.76 was the fastest 200 ever run in Britain, and he beat Wallace Spearmon of the United States by more than half a second.

"I definitely want the double in Beijing, but my coach makes all my decisions for me," Bolt said.

"I'm just waiting on him to decide. I'm definitely ready - I've been ready for two months now.

"People may try to pressure me, but I don't pressure myself because I look to do my best all the time."

Mills deems the 200 a much easier event for Bolt, as Asafa Powell and Tyson Gay have more experience in big events in the 100.

"The 200 is the easier race based on his performances so far - it's not as competitive as the 100," Mills said. "There's always the temptation to take what you are sure of. If you run the 100 you have to be consistent with your technique."

Some inconsistency

The 21-year-old Bolt showed some of his inconsistency on Tuesday, when his weak start at the DN Galan in Stockholm saw him lose to Powell by one-hundredth of a second.

"In the 100m you need to be an experienced person at this level," Mills said. "Things that happen to you like at Stockholm - getting left at the start and he just got up and run and abandoned all strategy - hat is the response of an inexperienced runner.

"The 100 we need to work out and master and we have 15 days to declare to the (Jamaican) association."

Bolt embarked on the 100 to improve his speed in 200, but it "took off like a roller coaster" after setting the world record of 9.72 on May 31, breaking Powell's mark of 9.74.

Bolt, who skipped Friday's 100 at Crystal Palace, said his confidence wasn't jolted by Tuesday's defeat and is ready to take on Powell and Gay.

"It's worth more to beat the best to become the best," he said.

No temptation

Mills, who once coached doping-tainted British sprinter Dwain Chambers, said he thinks Bolt will never be tempted to enhance his performances with illegal substances.

"We can't shield him, he has to shield himself, and we try to educate him on proper values," he said. "Most of the athletes who have got into trouble have gone abroad to train or go to school. We believe our athletes don't need it. We are talented enough."