London:
Usain Bolt still has more to give this year, saying on Tuesday he's running at "85 percent" of his potential going into his final meet before next month's world championships.
"Yes, I'm not in the best shape of my life but I'm still in good shape," Bolt said ahead of the two- day London Grand Prix. "I think I'm probably close, probably 85 percent."
Bolt runs in the 100 meters Friday, one week after he ran a season-best 9.79 seconds in poor weather in Paris - just .10 outside his world record run when slowing near the finish of the Olympic final last August.
After having surgery on his left foot following a car accident in April, Bolt believes the interruption to his training means he won't be at his best until the August 15-23 worlds in Berlin.
Still, he would not rule out a record time at the Crystal Palace track on Friday.
"You never know for me what's possible if the weather is good - I doubt it will be. I'm bringing the rain wherever I go," he said. "For me, it's not all about time, it's all about performance. It's just to see where I'm at and what I need to do."
Bolt's biggest challenge Friday should come from Asafa Powell, a teammate on Jamaica's world record 4x100 relay team in Beijing.
Powell was the last man to beat Bolt, winning in Stockholm exactly a year ago, and has a best of 9.72 set last September.
"He's a great athlete and a great performer," Bolt said of Powell. "Our (personal best times) are not very far apart."
Athletics fans must wait until Berlin for a showdown over 100 between Bolt and Tyson Gay, the current world champion and fastest man in the world this year.
"I have never backed down from any challenge out in front of me," Bolt said. "Rivalry is always good. It excites me in a way to know that there's somebody out there that could beat me."
Gay's 9.77 in Rome earlier this month matched his own United States record, while the 26-year- old from Kentucky posted a 19.58 over 200 in New York in May that is one-hundredth faster than Bolt over the distance this year.
Gay will run the 200 at the London GP on Saturday, before the two step on the same track for a 4x100 relay that closes the meet.
Bolt said he would analyze his two 100 runs in London to "get it right" for the worlds, but would concentrate more on his 200 before Berlin.
"I didn't do so much work after my accident in Jamaica," he said, though the damage was done by stepping on thorns walking away from his wrecked BMW. "I had to do mostly 80 meters, 110s. Leaning into the corner was really hard for me. I didn't do anything like curves. I have got a lot of catching up to do."