Now that everyone knows which two races Allyson Felix will run, it's time to find out if Tyson Gay is fit enough to win even one.

Over the next 10 days in Eugene, two of America's best-known sprinters will try to qualify for a trip to the London Games, but while Felix heads into Olympic trials at the top of her game, Gay remains a question mark after months of struggling with injuries.

"Thirty," said Gay, who turns 30 in August, when asked how he's feeling.

He has spent most of the past year on the shelf with a hip injury. His first race back was in New York earlier this month, where he ran 10.00 seconds into a headwind and said he felt good. The men's 100, however, might be the most competitive event at Olympic trials, where three spots are available in each event and there are no concessions made for injuries, false starts or anything else.

Among those Gay will have to beat are 2009 national champion Michael Rodgers, Olympic bronze medalist Walter Dix, 2004 Olympic gold medalist Justin Gatlin and two-time Olympian Darvis Patton. And if Gay somehow gets through that gauntlet, Jamaicans Usain Bolt and Yohan Blake will be waiting in London.

"If I make the team, it would be good," Gay said. "Part of me just says, 'These guys are not going to sit down and let me come back after a year and give it to me easy.'"

Gay's first race is Saturday, while Felix takes to the track Friday.

Felix, a three-time world champion at 200 meters, is still trying to win her first Olympic gold at that distance. She tried the 200-400 last year at world championships in Daegu, South Korea, but finished second in the 400, then followed with a fatigued third-place finish in the 200.

"Daegu helped me see for myself how doing the 400 first, then coming back trying to sprint, how that worked," Felix said.

Not well, as it turned out. So this time, she opted for the 100-200 double.

"I said from the beginning that what's most important for me is what's going to help me run my best 200," Felix said. "Bobby (Kersee, Felix's coach) felt running the 100 helps my 200, and for me, that's what it's all about."

But while she was making her decision, another American star, Sanya Richards-Ross, was quietly going about setting up her own chance at the double that Felix opted not to try. Richards-Ross, whose specialty is in the 400, holds the world's fastest time in both the 200 and 400 this year and will try to qualify for both. Like Felix, Richards-Ross has unfinished business: She was a favorite in the 400 in Beijing but slowed at the end. She finished third, a result that left her crying under the stands at the Bird's Nest.

The reason she's trying for the 200-400 while Felix chose not to is that Richards-Ross' key event is the 400 — the one that comes first on the schedule at both the Olympics and at trials.

"Whatever happens in the 200 will be extra, a lot of fun," she said. "If it were flipped, I'm almost sure Coach (Clyde) Hart wouldn't want me to do it."

In the men's 400, LaShawn Merritt, running well after serving a 21-month ban for using a banned male-enhancement product that also has been identified as a steroid precursor, is the defending Olympic champion and trying to stay ahead of 2004 Olympic gold medalist Jeremy Wariner. Merritt calls the episode that led to his punishment an embarrassment.

"It happened. I had to deal with it, with the poor judgment call on my end, and it's over," he said.

It's track and field, so of course there's more than one doping story to tell.

Gatlin was the 2004 Olympic champion but later served a four-year doping ban, a ban he claims is the result of a masseuse using a testosterone cream on him without his knowledge.

"Everyone has coined the phrase as 'redemption,'" Gatlin said when asked how it feels to return to Olympic trials after missing 2008. "For me, it's almost like a welcome-home party. I don't think anybody had the expectation of me coming this far. But just to come back and be able to compete was a victory within itself."

Up to 120 spots on the Olympic team will be handed out by the end of competition on July 1. The first three went to Amber Campbell, Amanda Bingson and Jessica Cosby in hammer throw, held Thursday at a specially constructed hammer cage up near Portland.

Among the other key events to watch:

— Women's 100 meters, where world champion Carmelita Jeter has this year's best time and the best chance of breaking up Jamaica's dominance in the women's sprints.

— Women's 100 hurdles, where the most recognizable athlete, Lolo Jones, is anything but a shoo-in to make the top three and earn a chance to compete for the gold she lost when she fell on the ninth hurdle in Beijing. Dawn Harper won the race that day and remains America's top hurdler.

— Decathlon, where the Americans have a realistic chance of going 1-2-3 in London, if defending champion Bryan Clay stays healthy, two-time world champion Trey Hardee's elbow holds up after major surgery and last year's world runner-up Ashton Eaton lives up to his potential.

— The long-distance races will be headlined by Bernard Lagat and Galen Rupp in the 5,000, Matt Centrowitz and Jenny Simpson, both surprise medalists in the 1,500 last year in South Korea, and, of course, Lopez Lomong, whose inspirational journey from a "Lost Boy" of Sudan to American Olympian helped earn him the role of U.S. flag bearer at the 2008 Games.

The weather forecast for the first weekend in Eugene calls for highs in the low 60s and a good chance of rain. In other words, it could feel very much like London, which doesn't bother too many people at this stage.

"For me, I don't care if it's raining, snowing," Richards-Ross said. "I've been waiting for this for four years."