Once more, Michael Phelps dives into Olympic waters
On Saturday,Michael Phelpswill turn 27. No surprise, he'll spend the birthday where he's spent much of his previous 26 years: in a pool, chasing gold.

This time, it will be in Omaha, Neb., where the Olympic qualifying trials begin Monday and where Phelps will begin to answer a question that has trailed him for the past four years: How will he possibly top his golden, eight-for-eight performance of Beijing?

"What Michael has done is insane. I think people now take gold medals for granted," said fellow swimmer Natalie Coughlin, herself among the most decorated Olympians ever.

Phelps has resolutely kept secret his game plan for the London Olympics, which open July 27 — which races he hopes to swim in his fourth and final Games, as well as any ambitions for sealing his legacy before he exits competitive swimming.

"Obviously there are so many things that I want to do, and for the competitive part of my career, I don't have a very big window to accomplish them," Phelps told reporters in Omaha on Saturday. "Those are goals I think I can accomplish. I've always said I want to be the first to do something. You guys can use your imagination; I'm not going to state them."

Phelps has said, however, that he will not try for eight gold medals again.

If adding another "most" to his list of accomplishments matters to him, London could provide that: With 16 medals from Athens and Beijing, Phelps needs three more to surpass the record of Russian gymnast Larisa Latynina. She won 18, including nine gold, during the 1950s and '60s, and gave Phelps, with whom she posed for a photo shoot in New York, a non-Olympic medal for good luck in London.

"It was probably one of the coolest things I've received so far," Phelps said, noting what "an honor" it was to meet such a significant figure in Olympic history.

That he is part of that pantheon is surely not lost on Phelps. For all the year-round attention Phelps has brought to the sport, the quadrennial Games remain swimming's biggest stage, and its biggest star is expected to further solidify his standing in London.

"The only thing that matters for Michael is the Olympics. That's where a swimmer's legacy is set in stone," said Rowdy Gaines, the NBC swimming commentator and three-time Olympic gold medalist.

Gaines said he thinks Phelps feels a sense of ownership of certain races — his signature 200-meter butterfly, the demanding 400-meter individual medley — and that could provide clues to what he hopes to swim in London.

Phelps and Bob Bowman, his longtime coach, have indicated that six or seven races in London would be a safe bet. Assuming that Phelps makes the three relay teams that were part of his Beijing lineup, that would mean no more than three or four individual events.

But which three or four?

He has signed up for seven races at the trials in Omaha, but swimmers often register for more events than they intend to swim, giving themselves more chances to make the team should they falter in early swims. The top two finishers in each race make the Olympic team.

The trials, and the Olympics, open with a race that both defines and bedevils Phelps: the taxing 400-meter individual medley, in which he smashed his world record to win his first gold in Beijing.

He vowed never to swim it again but has backed off from that repeatedly, swimming if not winning it multiple times since 2008.

Someone who could challenge Phelps in the 400 IM, Tyler Clary, said Saturday that he didn't think Phelps would enter the event here because he knows that the United States could field a "fantastic" team without the Baltimore swimmer. He clearly was referring to Ryan Lochte and himself, who denied Phelps a spot in the 400 IM finals in the Pan-Pacific Championships in 2010.

Phelps would not say whether he would swim the 400 IM on Monday.

He also has signed up for the 200-meter individual medley and might have particular motivation for swimming that in London: He lost his world record in that race in 2009 to his main American rival, Lochte, who then reset that record with an even faster time last year — again over Phelps.