Tyson Gay is gunning for Usain Bolt in Berlin

ANYONE who thinks the World Championships 100m final is a foregone conclusion had better think again after a breath-taking performance from Tyson Gay at the US Championships.

ON THE MARCH: Tyson Gay clocks a wind-assisted 9.75 at US Championships and is gunning for Usain Bolt in Berlin

The 26-year-old clocked 9.75 seconds in the heats in Eugene, Oregon, 0.02 secs faster than Usain Bolt's 9.77 seconds, clocked earlier this month in Ostrava.

While both times were wind-assisted, both are in blistering form - Bolt's world record of 9.69 secs - set on the way to Olympic gold in Beijing - looks under threat and contrary to popular belief, the Jamaican will not have it all his own way in Berlin next month.

Gay is the reigning world 100m and 200m champion but was well below-par at the Beijing Olympics, having suffered a hamstring injury at the US trials.

That injury was picked up in the 200m trials, having already clocked a wind-assisted 9.68 secs in the 100m, and having had to sit back at watch Bolt's Olympic fireworks, Gay revealed he will not be making the same mistake again.

"It's been the plan for the last month or so to only run just one race at the trials," said Gay, who earlier this year clocked the third-fastest ever 200m time at the Reebok Grand Prix.

"I'm just trying to stay healthy and get ready for the World Championships. I'm looking forward to a fast race there.

"You have got to run 9.59 to beat Usain, that's how I look at it, I have the mechanics. I have the coaching.

"I've ran a wind-aided 9.7 and he has ran a wind-aided 9.7. We are both showing great fitness, but to be honest my race here was horrible.

"The false start kind of threw me off. I got out of the box and held on to the field until about 60 metres. Then I was able to pull away through the finish line."

"I knew it was wind aided, so it wasn't going to get in the books. At the same time I got to know that I am able to turn over that fast. I'll be able to do that when I execute. I had the right rhythm, but I didn't feel that in the race."

Gay has already booked his place in Berlin in both the 100m and 200m due to the fact he is the reigning champion in both events.

Meanwhile, Olympic decathlon champion Bryan Clay has become the first major casualty of the World Championships after a hamstring injury forced him to with draw from the trials.

The 29-year-old, who collected the world crown in 2005, missed out two years ago in Osaka through injury, and will be forced to forgo the chance to recapture the title in Berlin.

"It's a tough decision. But if somebody's going to beat me, I want it to be when I'm having my best day," he said.

"I think if I had a few more days I could have made it happen."

Meanwhile, in the 400m Sanya Richards, fresh from clocking the fastest time of the year so far, eased through her heat in 51.38 secs.

"I always say that the first round is kind of the hardest one. I just wanted to do enough to win so I was happy," said Richards, who looks set to go head to head world and Olympic champion Christine Ohuruogu in Berlin.

"I feel really good. My body is feeling great. My training is right where it needs to be. I hope I can do something really special in the final."