PARIS: Puerto Rico's Jasmine Camacho-Quinn opened her Olympic 100 metres hurdles title defence by posting the fastest time in the heats on Wednesday, as all the favourites moved onto the semi-finals.
Nigeria's world record holder Tobi Amusan and American Masai Russell are among those trying to knock her off the throne, while home hope Cyrena Samba-Mayela is among France's brightest hopes for an individual track gold.
Camacho-Quinn showed she was in no mood to let that happen, though, as she glided over the barriers to finish in 12.42 seconds, three tenths clear of Britain's Cindy Sember.
The first three in each heat and the next fastest three across all the races moved on.
Amusan arrived in peak condition at the Stade de France after the Court of Arbitration for Sport cleared her of an anti-doping rule violation weeks before the Games kicked off, rejecting appeals from World Athletics and the World Anti-Doping Agency.
She took the lead in her heat at about the halfway mark and easily cruised through the finish in 12.49, while American Alaysha Johnson (12.61) was second.
Russell, who has the fastest time of the year, tuned out the noise to tie for first with the Netherlands' Nadine Visser in 12.53 as the Paris crowd cheered wildly for Samba-Mayela (12.56), who finished third to reach Friday's semi-final.
Jamaican Danielle Williams (12.59), who beat Camacho-Quinn for world gold in Budapest last year, made easy work of her heat out of lane nine, as Ireland's Sarah Lavin was second in 12.73.
Ackera Nugent of Jamaica crossed the line in the final heat of the day in 12.65 ahead of Bahamian Devynne Charlton (12.71) in second.-- Reuters