KINGSTON, Jamaica -- Jamaican top sprinter Asafa Powell wants to silence his critics and avenge his defeat to American Tyson Gay when the sprinters clash at the London Grand Prix on July 25.

Powell, the former world 100-metres record holders with 9.74-seconds, made his comments during an interview on a local television channel in Kingston, Wednesday night.

"I just want to get this behind me, because people have Tyson Gay name in their heads, saying Asafa can't beat him," Powell said.

"I just want to get this out of their heads," he added.

Meanwhile, Powell, the only man to equal world record three-times, twice in one season (9.77), left the island Wednesday for a training camp in Italy where preparations for the Olympics will go into full gear.