Beijing:Michael Phelps advanced out of the Olympic 200-meter freestyle preliminaries on Sunday, qualifying fourth-fastest about nine hours after the American won a gold medal in the 400 individual medley.
Phelps never led in his heat and finished in 1 minute, 46.48 seconds, well off his world record set at last year's world championships.
"Tonight was just a race to get into tomorrow," Phelps said. "I just try to conserve everything and make it into the semifinal. I try to bank as much rest as I can tonight recover and sleep and try to warm down and get out of here as fast as I can, so I'm not getting so run down."
Dominik Meichtry of Switzerland led the way in 1:45.80. Jean Basson of South Africa was second-quickest in 1:46.31, followed by Brent Hayden of Canada.
Phelps was still on an emotional high from winning the first swimming medal of these games, and doing so in world-record time. That put him on his way toward breaking Mark Spitz's record of seven gold medals in a single games.
Kirsty Coventry of Zimbabwe was the fastest qualifier for the 100 backstroke, where the top four women all swam under 1 minute.
The Olympic record set by Natalie Coughlin four years ago in Athens was broken in each of the last three heats, with the mark eventually belonging to Coventry, who touched in 59.00 seconds. She was the silver medalist in Athens behind Coughlin. Earlier Sunday, Coventry won a silver medal in the 400 IM.
"I was still running off the adrenaline and hyper from this morning," Coventry said. "I didn't have to build up too much energy."
Reiko Nakamura of Japan was second-quickest in 59.36, while Anastasia Zueva of Russia also went under the old Olympic mark in 59.61.
Coughlin, who won a silver medal earlier Sunday in the 400 freestyle relay, advanced to the semifinals in fourth, with a time of 59.69, well off her world record of 58.97.
"I definitely have my work cut out for me," Coughlin said. "The 100 back is probably the quickest progressing event in the past year in swimming. There's a lot pressure on me, but I'm going to enjoy it as much as possible."
Laure Manaudou of France, the bronze medalist in Athens, was fifth.