Updated

Lolo Jones of the United States posted the second-fastest time in heats for the women's 100-meter hurdles Monday, moving her into the semifinals at the London Olympics.

Jones ran in the last of six heats and won the race with a season-best time of 12.68 seconds. Only Australia's Sally Pearson was faster on the day, taking the fifth heat with a time of 12.57 seconds. Pearson won last year's world championships and earned silver four years ago in Beijing.

The 30-year-old Jones is out for redemption in London after crashing out in this event at the Beijing Games. She was leading the final race four years ago before stumbling over the final hurdle and placing seventh.

"I'm going to do my best and fight for gold," Jones said after her heat. "But I don't ever bet on the hurdles."

Kellie Wells of the U.S. also won her heat and finished .01 seconds slower than Jones. Dawn Harper, winner of the 100 hurdles at the U.S. Olympic trials, posted a time of 12.75 to place sixth in qualifying.

Meanwhile, 2009 world champion Brigitte Foster-Hylton of Jamaica failed to qualify after hitting the fifth hurdle and placing seventh in her heat. Like Jones at the 2008 Olympics, Foster-Hylton was leading the race when she hit the hurdle

The semifinals and final of the 100 hurdles are set for Tuesday night at Olympic Stadium.

Qualification rounds also were held Monday morning for the men's discus and women's shot put, while heats were run in the men's 800 meters and the women's 1,500m.

Shannon Rowbury of the U.S. qualified for the semifinals of the 1,500 meters, posting the seventh-best time with a run of 4 minutes, 6.03 seconds. American Morgan Uceny also qualified, running .84 seconds slower than Rowbury, while Ethiopia's Abeda Aregawi had the best time in the heats at 4:04.55.

Nick Symmonds and Duane Solomon of the U.S. both moved onto the semifinals in the men's 800 by winning their respective heats. Symmonds logged a time of 1:45.91 and Solomon was .14 seconds slower. Khadevis Robinson, runner-up to Symmonds at the U.S. Olympic trials, failed to make it to the semifinals.

Sudan's Abubaker Kaki was tops in 800 qualifying with a run of 1:45.51.

Michelle Carter was the lone American to make it to the final round of the women's shot put, which is set for Monday night. Carter placed eighth with a throw of 18.63 meters. Nadzeya Ostapchuk of Belarus had the best toss in qualifications with a distance of 20.76 meters.

Estonia's Gerd Kanter had the longest throw in qualifying for the men's discus final with a mark of 66.39 meters. Jason Young, Lance Brooks and Jarred Rome of the U.S. all failed to make it Tuesday's medal event.