KINGSTON, Jamaica (AP) -- With Usain Bolt waiting for his first sprint of Jamaican Olympic trials, defending Olympic champion hurdler Melanie Walker cruised to a victory in her preliminary heat Thursday, finishing the 400-meter race in 54.88 seconds.
Walker was one of the few big-name athletes on the track during a morning session that lasted about an hour. Her time was 1.04 seconds better than the next-best finisher, Kaleise Spencer.
There were five qualifying heats in the men's 100. The best time was 10.54 seconds by Ramone Nichol.
Bolt was slated to run in quarterfinal heats Thursday evening, along with world champion Yohan Blake and former world-record holder Asafa Powell.
Veronica Campbell-Brown, the 200-meter Olympic champion who failed to qualify for the 100 in 2008, will race Thursday, as will Olympic champion Shelly-Ann Fraser-Pryce.