Michael Phelps and Ryan Lochte moved on in the men's 200-meter individual medley Wednesday morning, hours after they both chipped in to get Phelps the all-time Olympic medal record.
Lochte, the world record holder, swam the second-fastest heat behind Laszlo Cseh of Hungary and Phelps was fourth.
Phelps won two medals Tuesday night, a silver in the men's 200-meter butterfly and a gold in the 800 freestyle relay, but will not swim in a final Wednesday.
"I did not really get much sleep last night," he said. "I did not warm down at all."
He is the two-time defending gold medalist in the 200 IM. The final Thursday night, if both swimmers make it (which they should), will be the second head- to-head matchup between Phelps and Lochte at the Aquatics Centre.
Lochte won the 400 IM Saturday in the first medal race here and Phelps was fourth, the first time he finished off an Olympic medal podium since he was 15.
The final of the men's 200 backstroke is about 30 minutes before the 200 IM on Thursday. Lochte also had heats for that race Wednesday morning and swam the second-fastest time behind Tyler Clary.
"The double is going to be tough but I've done the training so I feel good," said Lochte.
Clary, of course, is the U.S. teammate who criticized Phelps' training in a newspaper article weeks before the London Olympics started. Phelps has said Clary apologized. And a day after Phelps won his 19th Olympic medal, there wasn't much to be critical of.
"He's won more medals than any Olympian in history," said Clary. "That should speak for itself. The guy's an incredible athlete."
Clary said it was "pretty cool" that U.S. President Barack Obama sent Phelps a tweet early Wednesday morning London time.
The president's tweet -- "Congratulations to Michael Phelps for breaking the all-time Olympic medal record. You've made your country proud." -- was signed "bo" to indicate it was from Obama himself.
Also Wednesday morning, the U.S. qualified second behind Australia in the women's 800 free relay and Rebecca Soni had the best time in heats for the 200 breast. Jessica Hardy moved on in the women's 100 freestyle while China's Tang Yi swam a 53.28 for the fastest heat.
One of the marquee swimming events at the Summer Games is set for the evening when top qualifier James Magnussen of Australia, Nathan Adrian of the U.S. and world record holder Cesar Cielo of Brazil will be among the eight swimmers in the final of the men's 100 free.
Japan's Kosuke Kitajima will try to win the men's 200-meter breaststroke for the third straight Olympics, which would make him the first male swimmer to win the same individual event in three consecutive games.
Americans Kathleen Hersey (the fastest qualifier) and Cammile Adams will go in the final of the women's 200-meter butterfly and medals will be given out in the women's 800-meter free relay.