-- Four years ago, Ed Moses won a silver medal in the 100-meter breaststroke in Sydney, and added a gold in the 400 medley relay. Sunday night, though, he was pondering whether, at 24, his swimming career is over.

"I don't know," Moses said. "I can't answer that right now."

Moses finished fourth in the 200 breaststroke at the U.S. Olympic swimming trials, well off the world-record pace set by the stroke's new dominant force, Brendan Hansen. Thus, Moses's trials are over, and he didn't make the Olympic team.

All week, Moses, an asthmatic, said that the pool at the Long Beach Aquatic Center didn't agree with him. He said he consulted with a doctor, who said there might be a chemical in the pool that restricted his breathing to anywhere between 60 and 70 percent of normal capacity.

"He said it's like swimming with a straw in my mouth," said Moses, a native of Burke and a former swimmer at the University of Virginia. "But I'm not going to go out there and not bust my [butt]. There's a lot of people who have sacrificed like me. I'm not going to go out like a chump like that. I came here to do something."

Yet he couldn't do it. His time of 2 minutes 14.12 seconds was more than five seconds behind Hansen. It was Moses who used to dive in the pool with those kinds of records in mind.

"It's 100 percent disappointing," Moses said. "My time when I was 19 would've made the Olympic team five years later. I put myself in a league above everybody else. I'm sure other people do, too. I've built up a reputation every time I'm out there I'm going to try and break the world record, and I wasn't on the same scale" as Hansen.

Moses said he wanted to investigate what might have caused his breathing problem before deciding whether he'll retire. He said he thinks other people at the meet had the same problem.

"It's something I've got to look into," he said. "I'm at a huge disadvantage with that."

Thompson Not Quite a Sure Thing

Jenny Thompson spent Friday and Saturday almost like a typical weekend "relaxing, staying off my feet, hanging out." Thompson could act that way, because Thursday night at the U.S. Olympic swimming trials, she all but guaranteed herself a trip to Athens by finishing second in the 100 butterfly. Still, she has high hopes for her remaining individual event, the 100 freestyle, the finals of which are Monday evening.

Yet if Thompson is to make the team in the 100 free -- first place is guaranteed a spot, and second doesn't officially make it until after the completion of the trials -- she'll have her hands full. The American record holder, Natalie Coughlin, looked strong again Sunday, finishing her semifinal heat in 54.30 seconds. Kara Lynn Joyce was second, with Thompson third in 54.94. The top four finishers Monday will make up the 400 relay team.

Peirsol vs. Phelps Is One to Watch

With all the hype around Michael Phelps at these trials, it's worth remembering that Phelps likely will not be the favorite in one of his finals Monday night, when he'll swim the 200 backstroke against Aaron Peirsol, who not only holds the world record but who hasn't lost in the event since the 2000 Olympics in Sydney. Peirsol already won the 100 backstroke at the trials, but the 200 is his best event, and he set an American record in the semifinals -- 1:55.33, just .18 off his world mark.

"My goal isn't to take any of Phelps's glory away," Peirsol said. "It's just to preserve my own."