Olympic and world champion Usain Bolt attends a press conference in Rome, capital of Italy, May 24, 2011. Bolt will make his season debut in Thursday's Rome Golden Gala, part of the IAAF's Diamond League series. (Xinhua/Wang Qingqin)

World 100-meter record holder Usain Bolt said on Tuesday that he is "slightly nervous" for the first time in his career, as he prepares to compete his first race over nine months in the Rome Golden Gala meet.

The Olympic champion, who ended his two-year unbeaten streak last August with back and achilles' tendon injuries after losing to American Tyson Gay in Stockholm, will face compatriot Asafa Powell and France' s Christophe Lemaitre in the third Diamond League meeting on Thursday.

"For the first time I'm slightly nervous - I haven't run in so long," Bolt said. "I'm always calm and relaxed. As I said I'm a little bit nervous, but I know I'm getting in shape. Me and my coach have done a lot of work leading up to this race."

The sprinting phenomenon said the loss to Gay led to "absolutely nothing" changed.

"You lose some and you win some. You never win every race in your entire career. Last season wasn't my best season. It was kind of my season downtime for me," he said.

"This season is back to business. I want to prove to the world that I'm still the best.

Bolt said his aim for the season is to win at the Aug. 27-Sept. 4 world championships in Daegu, South Korea.

"I'm not really expecting anything, I'm just going out there to see where I'm at and see what I need to do for the world championships," he said. "These meets are stepping stones for the world championships. My whole focus this year is just to work toward the world championships."