Jamaican track star Usain Bolt yesterday acknowledged he has had a rocky build-up to the London Olympics, but declared himself “ready to go” in his bid to defend his double sprint titles.

“I’m always ready,” said Bolt. “It’s all about championships. I’ve had slight problems, but I’m ready to go.”

Fitness concerns and losing over both the 100 and 200m to training partner and compatriot Yohan Blake in the Jamaican Olympic trials raised serious doubts about Bolt’s ability to defend his titles.

But Bolt, speaking at his first pre-Olympic press conference alongside fellow sprinter Asafa Powell, said: “I’m going to focus on going out there to win.

“My back was a little stiff and it affected my hamstring but I’m over that. I’ve been training for the past two-and-a-half weeks and everything is alright.”

“I don’t think it will be the end of the world if I lose.

“I would definitely be disappointed if I was second. Mentally though I am always strong. I have a great team around me.”

Bolt refused to pick out any one sprinter as his main rival, saying: “Who is the danger man?! Not one specific one but the seven men in the blocks.

“There is one great moment, there is never one single person.”

Bolt received an extra boost when Jamaica Olympic Association president Mike Fennell named him as the country’s flag bearer for Friday’s opening ceremony.

“It’s an honour to carry the flag for my country. I would do anything for my country,” said Bolt.