( L - R ) Powell, Gay - File photos

PHILADELPHIA:

ASAFA POWELL, the world's fastest man, and American world sprint double champion Tyson Gay could face-off tomorrow in the USA versus The World clash at the 114th Penn Relays here at Franklin Field stadium.

They were scheduled to clash at last week's Mt. San Antonio College Relays but Powell pulled out at the last minute for reasons still unknown.

Meanwhile, World Championships 400m bronze medallist Novlene Williams, Kenia Sinclair and Sherone Simpson, the fastest woman in 2006, are also down to compete on tomorrow's final day.

Relay

The men's 4x100m team will be chosen from Powell, Marvin Anderson, Michael Frater, Nesta Carter and Dwight Thomas; while the women's team will come from Nadine Palmer, Peta-Gaye Dowdie, Aleen Bailey and Kerron Stewart.

Former world No. 2-ranked Michael Blackwood, Sanjay Ayre, Adrian Findlay and Dewayne Barrett will team up in the men's 4x400m. Williams, Kaliese Spencer, Simpson, Sonita Sutherland, Melaine Walker, Davita Prendagast and Schericka Williams are listed for the 1600m relay, from which the final team will be chosen today. The Sprint Medley combines two 200m legs, one 400 and a 800m, which Sinclair will run. The other members will be selected today.