Michael Phelps readied for an Olympic showdown with Ryan Lochte in the 200-meter individual medley, qualifying sixth while his good friend and rival posted the fastest time Wednesday night.
Phelps ended a golden day at the pool by winning his preliminary heat in 1 minute, 58.65 seconds, good enough to move on to Thursday morning's semifinals.
"I'm just trying to get through everything," he said. "It's a lot of racing and it's not easy."
Swimming one heat earlier, Lochte finished in 1:58.15. Laszlo Cseh of Hungary, already a two-time silver medalist behind Phelps in the 400 IM and 200 butterfly, was third overall in 1:58.79.
Earlier in the day, Phelps claimed two more gold medals, making him 5-for-5 at these games, with world records in each victory. Overall, his 11 career gold medals make him the winningest Olympian in history.
Lochte pulled double-duty Wednesday night, preparing for his two biggest individual races in Beijing.
He and Aaron Peirsol set up a rematch in the 200 backstroke, with the Americans qualifying 1-2 for the event in which they share the world record.
Lochte's time of 1 minute, 56.29 seconds was just 0.06 seconds ahead of Peirsol, who clocked 1:56.35 in the prior preliminary heat.
Markus Rogan of Austria, the silver medalist behind Peirsol four years ago in Athens, was third-quickest in 1:56.64.
Defending champion Amanda Beard failed to get out of the 200 breaststroke prelims. The former Playboy cover girl's time of 2:27.70 was a whopping 2.57 seconds off her personal best and left her 18th.
Lochte ended Peirsol's seven-year winning streak in the 200 back at last year's world championships in Australia, where he also took away Peirsol's world record. Rogan was third.
The American duo resumed their rivalry at the U.S. trials in July, when Peirsol avenged his loss Down Under. The two were stroke for stroke the entire race, but Peirsol lunged to the wall just ahead of Lochte, tying the mark set by Lochte in Australia.
Their shared world mark of 1:54.32 could be in jeopardy in Friday morning's final. Peirsol, the 100 back champion in Beijing, will try to complete a sweep of the backstroke events for the second consecutive Olympics.
"It was wonderful enough to do it in the 100," he said. "If I could do it in the 200, it would be a dream come true. But if I can't, it will in no way be a blemish on my career."
Adding to Beard's indignity in the 200 breast, her Olympic record set four years ago was erased by teammate Rebecca Soni, who led all qualifiers in 2:22.17, more than a full second better than Beard's mark of 2:23.37.
"It felt great. I didn't even know I had broken an Olympic record," Soni said. "It reminded me that I am in the right place and not to stress."
Beard and Soni had trained together at the University of Southern California before Beard left a couple weeks ahead of the U.S. trials because of what her former coach called a contentious atmosphere.
"What can you do?" Soni said. "We swam together a little bit and I got to know her. She is a great girl."
Soni set up a rematch with Aussie Leisel Jones, second-fastest in 2:23.81. Mirna Jukic of Austria was third in 2:24.39. Jones, Soni and Jukic were the gold, silver and bronze medalists in the 100 breast Tuesday.
Beard was 0.58 seconds out of grabbing the 16th and last spot for the semifinals. The 26-year-old American was a three-time medalist in the event since making her Olympic debut in 1996.
An angry Beard strode quickly past reporters without a word.
Hanna-Maria Seppala of Finland qualified fastest in the women's 100 free preliminaries, clocking 53.60 seconds.
Britta Steffen of Germany was second in 53.67 and Marleen Veldhuis of the Netherlands was third in 53.76. American Natalie Coughlin, the bronze medalist in Athens, won her heat in 53.82 and was fourth overall.
Coughlin already has a full set of medals at these games, having won gold in the 100 back, silver in the 400 free relay and bronze earlier Wednesday in the 200 individual medley.
"The times were very fast," she said. "Luckily, I was next to the world record-holder in the preliminary, judging off her I think I did pretty good."
Libby Trickett of Australia, the world champion who owns the world record of 52.88, was sixth (53.99). She will be hard-pressed to complete the 50-100 sprint double for the first time since the Dutch swimmer Inge de Bruijn did so eight years ago in Sydney.
Trickett predicted a time of 53 seconds and change will be needed to make the final.
"That's amazing in itself," she said. "To think that (time) won it all in Sydney, but that's what it will take just to get to the final here. Hopefully I'm making the finals this time."
American Lacey Nymeyer (14th) also moved on to the semifinals.