Usain Bolt answered questions over his fitness ahead of the world championships with a season's best of 9.87 seconds in the 100m with a workmanlike performance at the London Anniversary Games on Friday.

With just under a month to go before he defends his world 100m and 200m titles in Beijing, the Jamaican showed he had recovered from a pelvic injury that has disrupted his season, although he was left with plenty to ponder in the rain-lashed capital.

I am still number one and until I retire that's the plan

Usain Bolt, World 100m, 200 record holder

The world's fastest man shook off the rust from his layoff - this was his first 100m for over three months and first competitive race since mid-June - to win his heat and the final in the same time, putting him equal sixth in the world this year.

But he had to eat up the ground in the second half of both races, winning the final by three-hundredths of a second ahead of American Mike Rodgers (9.90) and fellow Jamaican Kemar Bailey-Cole (9.92).

"I am still number one and until I retire that's the plan," said the double world champion.

"I was happy with what I did," added the six-time Olympic champion.

"I'm ready to go and I'm ready to win. In the final I got a really bad start, I kind of lost focus but I got it back. I know I could have gone faster if I had just got my start."

Meanwhile, Britian's Mo Farah received a huge ovation before and after winning the 3,000 metres in 7:34.66, the fastest time in the world this year.

Farah has been dogged by the doping allegations surrounding his coach Alberto Salazar but has not been accused of any wrongdoing.

"You can only do what you do best and that, for me, is running," he said.

Source: Al Jazeera and agencies