NEW YORK - Usain Bolt has admitted he needs to work on his start and finish in the 100 metres, yet the 21-year-old Jamaican is eager to test himself against world champion Tyson Gay in the Reebok grand prix on Saturday.

Usain Bolt, left, from Jamaica, listens as Tyson Gay, right, of the United States, speaks during a press conference in New York, Thursday, May 29 , 2008. Both will compete in the Reebok Grand Prix international track meet in New York on Saturday, June 1. [Agencies]

Bolt, world silver medalist behind Gay in the 200 metres, stunned athletics by running 9.76 seconds, the second-fastest 100 metres, at the Jamaica International on May 3 and will face the American over the distance for the first time on Saturday.

"My start is the toughest part of my race," the 1.96m tall Bolt told reporters on Thursday. "I think that's because I'm kind of tall. I'm working hard and hopefully I'll get it right."

Bolt's coach Glen Mills said his height worked against him at the start, but his ability as a 200 metre runner to sustain top speed made him a 100-metres force to be reckoned with.

"He's never going to be a great starter at that height," Mills said. "You just want to be in the race for the first 30 meters....to be in striking distance and take it from there.

"He has to work more than say a more explosive guy like Asafa (Powell) or Gay. He has got to do a lot of pushing off that track to get to top speed, like getting a car revved up. But once he gets there he's as good as anybody out there."

Bolt was also aware he needed to keep his concentration throughout the race and not ease off before the finish line.

"I was just looking to see what time I was running," he said of his run in Jamaica. "I wasn't expecting to run that time. So when I got near to the line I was just looking. I wasn't really slowing up, I was just looking at the clock. It is a bad habit."

IMPROVING SPEED

Bolt has been running the 100 metres to improve his speed for the 200 and the results have been impressive. He came within two-hundredths of a second of compatriot Powell's world record of 9.74 in just his third competitive race at the distance and was now looking forward to his showdown with Gay.