Gay overcomes sore hip to advance in US 100m

World silver medallist Tyson Gay survived a sluggish start and painful right hip to qualify second in his 100 metres preliminary at the US world championships trials on Thursday.

Gay, the year's fastest sprinter, clocked a wind-assisted time of 10.01 seconds to finish behind Ivory Williams as he pursues a rematch with Jamaican record holder Usain Bolt at August's world championships in Daegu, South Korea.

"My race was OK, the start was sluggish," said the out-of-breath US record holder. "I was a little jittery because I didn't want a false start."

Gay said he did not feel bad but wanted treatment on his hip to see how it reacted.

His time was the third best of the day behind a pair of 9.95s by Williams and Mike Rodgers, but it advanced him to Friday's semi-final. The final is also Friday.

The surprise of the round was disgraced sprinter Justin Gatlin, who is in the second year of a comeback from a four-year doping ban. The former Olympic and world champion looked strong in winning his preliminary in 10.08, equal sixth best of the day, to advance.

"I feel rusty, dusty," said Gatlin, who is running in his first US championship in five years.

"Last year I was more gracious and grateful," he said of a low-key, short 2010 season. "I felt like I was running for mayor... kissing babies instead of being focused, being that cut-throat kind of guy.

"(This year) I want to attack," said the 29-year-old.

Gay said he did not watch Gatlin's race and did not understand the fuss over his return.

"He came back last year so I think the drama is over with," said the world's second-fastest man behind Bolt.

The women's 100 preliminaries were also fast with Marshevet Myers clocking 10.87 seconds and top-ranked Carmelita Jeter a hundredth of a second behind.

Felix pleased

Allyson Felix eased through her opening race in the 400 metres, winning the preliminary in 51.79 seconds, fourth fastest time of the day.

"So far, so good," said the three-times 200m world champion, who is running the longer race this week before deciding if she will try a 200-400 double at the world championships.

She has a free pass to Daegu in the 200m as the defending champion but will need to finish in the top three in the 400m on Saturday to make the US team.

Defending world 400 champion Sanya Richards-Ross, who is also contemplating a 200/400 double in August, won her preliminary in 52.02 seconds but said she would not run Saturday's final.

Her concentration will be on the 200m this weekend and a top three finish for a spot on the American team.

US  indoor 400m record holder Francena McCorory had the day's fastest time of 51.46.

Olympic bronze medallist Shalane Flanagan won the women's 10,000m in 30:59.97 with local favorite Galen Rupp the men's winner in 28:38.17

Pentathlon world record holder Ashton Eaton set himself up for a big decathlon score with a personal best 4,604 points for the first five events. The 23-year-old led Olympic champion Bryan Clay by 408 points heading into Friday's closing events.

The trials continue through Sunday.