BARCELONA, Spain (AP) — It's The Missile vs. The Olympic Champion.
In a rematch.
The 100-meter freestyle, swimming's signature race, takes center stage Thursday at the world championships.
And if the results from the London Games are any indication, it's going to be decided by a tiny fraction of a second.
A year ago in the Olympic final, Nathan Adrian edged James "The Missile" Magnussen by 0.01 seconds — the smallest margin in the sport. And the American and the Australian were the only swimmers to break the 48-second barrier in Wednesday's qualification heats.
Magnussen led the morning heats in 47.71, then Adrian topped the evening semifinals in 47.95.
So who will win?
Well, let the pre-race jockeying begin.
"The 100 freestyle is a man's man event," Adrian said. "Anybody who can swim it, does. So I think there's going to be a lot of competition."
Magnussen, the defending world champion, disagreed.
"I think Nathan Adrian is still the favorite," Magnussen said. "He's the Olympic champion. He's the fastest into the final. So I would keep your eye on him.
"I'm looking forward to racing again on a big stage tomorrow night," the Australian added.
Magnussen was an overwhelming favorite at the Olympics, where Adrian's gold came as somewhat of a surprise. This time, both have pressure.
Both the Americans and the Australians struggled in the 4x100 free relay on the opening night of the pool competition, when the French passed the Americans for gold in the final lap, leaving the U.S. with silver and relegating the Aussies and Magnussen to fourth again, just like in London.
Adrian threw up on the medal stand after swimming the leadoff leg in the relay.
"Everybody has thrown up before," Adrian said. "People are making a bigger deal out of it than necessary. I threw up. I feel fine now."
He certainly looked fine in Wednesday's semifinals.
"It was the same time as I went leading off the relay," he said. "I swam it smarter this time. My body is a little more used to it."
Magnussen swam slower than he did in morning heats.
"I saw the first semi and it wasn't very fast so I thought I would just try to go out a bit easier the first 50 and I felt like it was reasonably controlled," he said.
While Adrian will be swimming the final in lane 4, which is reserved for the top qualifier, Magnussen will be over in lane 6 after advancing in only a tie for fourth with Vladimir Morozov of Russia.
"I've been in lane four and had successes and failure in lane four, so I don't think lanes really matter," Magnussen said. "But it will be a nice change to mix things up a bit."
So what time will it take to win?
Adrian and Magnussen agreed on about 47.5.
"I don't really like to focus on times but James is pretty consistently seven-mid," Adrian said. "(But) maybe it will take a seven-0, who knows?"
And who knows, maybe there will be a surprise winner.
Adrian's American teammate Jimmy Feigen qualified second in a personal-best 48.07 and is looking to bounce back after losing the lead in the anchor leg of the relay.
"Honestly, I was a little disappointed," Feigen said. "I'm happy with the time but I really would have rather had an effort like that in the relay. We probably would have come out with the first place instead of the second."
Having taken over Michael Phelps' spot in the relay, the 23-year-old Feigen is learning fast, and he'll be swimming next to Adrian in the final.
"He's a veteran of these situations," Feigen said. "So hopefully he can teach me the ropes and we can get a good finish tomorrow."
With world record holder Cesar Cielo sitting this race out, fellow Brazilian Marcelo Chierighini qualified third.
Then there's Morozov, a 21-year-old Russian who has lived in California since he was 14.
Morozov won gold at the recent World University Games in Kazan, Russia, in 47.62. Entering this meet, that was the second fastest time this year, behind only the 47.53 that Magnussen swam at the Australian trials.
When Morozov swept the 50 and 100 free titles at last year's short-course worlds in Istanbul, Russian media began comparing him to the legendary Alexander Popov.
But Morozov's idols were Americans.
"When I was getting into swimming more seriously, Popov was already done from the world stage," he explained. "So I never really got to look up to him. Maybe I looked up to Jason Lezak a little. I looked up to (Lenny) Krayzelburg, who swam backstroke. I actually swam 200 backstroke, too, at the time."
One other contender could be Fabien Gilot, who swam a 46.90 in the third leg for France in the relay. Although he qualified only sixth in 48.20, followed by Cameron McEvoy of Australia in 48.43 and Luca Dotto of Italy in 48.46.
"The point of having an eight-person final is that eight people can win," Adrian said. "Anybody. Seriously."
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