Start key to beating Bolt: Gay

EUGENE, Oregon: American world champion Tyson Gay believes he is capable of challenging Usain Bolt's 100m world record - if he can improve his start.

"Pretty much when I become more technically sound out of the blocks," Gay said on Thursday after running a wind-assisted 9.75 seconds in his first 100m of the season at the US World Championship trials.

"I have the mechanics. I have the coaching... it's there."