LAUSANNE, Switzerland (AP) — Tyson Gay is finally injury-free and says he has “no excuses” for not beating Usain Bolt.

The fastest man in the world this year, Gay acknowledged his frustration yesterday at dealing with hip, groin and hamstring pain while Bolt piled up world records and gold medals.

“It just was maddening for so long,” said the American, who won sprint double gold at the 2007 World Championships before Bolt started dominating the following year.

“It’s finally over and done with,” Gay told reporters ahead of his headline appearance in the 100 at the Athletissima Diamond League meeting today.

“I have no excuses, I have no pain. I feel good. I am over the mental part of being injured,” said the sprinter, whose 31st birthday next month falls on the eve of the Worlds opening in Moscow.

Now Gay wants Bolt, who skips Athletissima to run a 200 in Paris on Saturday, to arrive in Russia in the same great shape. Double Olympic silver medallist Yohan Blake is the actual world champion at 100 — after Bolt famously false-started in Daegu, South Korea — though the Jamaican number two has had a hamstring injury since April.

“I hope Usain stays healthy and may the best man win,” Gay said. “It’s no secret that this guy is a championship performer and you have to bring your ‘A’ game to beat him, or better than your ‘A’ game.”

Gay showed his readiness by winning the 100 and 200 metres at the US championships last month, clocking world-leading times of 9.75 and 19.74 seconds, respectively.

Confidence flows from his body after standing up in Des Moines, Iowa, to the same intense programme of heats, semi-finals and finals which await in Moscow.

“I felt me doing the double was a hump I had to get over myself. I hadn’t done it in five years,” Gay said.

Gay pointed to changes in his coaching set-up and approach, prioritising his body over going flat-out fast all the time.

“It just is all to do with trying to stay healthy,” said Gay, adding he is working only with longtime coach Lance Baumann and not — for now — with Jon Drummond, who joined the sprinter’s team ahead of his 2007 season. The new approach involves “taking things slower” and picking spots to post fast times in practice.

After seasons of Jamaican domination, at major events and on the Diamond League circuit, Americans can take centre stage today.