The second semi-final threw together the two American favourites for this title, in Ginny Powell and Michelle Perry, and provided what looked to be a definitive guide to the ultimate outome in the final, as defending champion Perry cruised through in 12.55, while Powell looked harried to scrape in to one of the four automatic qualifying slots in 12.67.

If anything, Canada looked as if it might have just as much chance of getting among the medals, as 2003 champion Perdita Felicien chased home Perry in a season's best 12.61, ahead of Vonette Dixon's 12.65 personal best.

European champion Susanna Kallur had won the first semi in 12.64 by 0.01 from Felicien's team mate Angela Whyte.

Delloreen Ennis-London (JAM), third in 12.67, and a third American LoLo Jones (12.68) complete the final line-up for the final on Wednesday night.

Osaka 2007 News Team/sd