(AP) LONDON - Michael Phelps barely qualified in the 400-meter individual medley on the opening day of Olympic swimming Saturday, squeaking into the final by seven-hundredths of a second.

"That one didn't feel too good," he said.

Phelps wasn't the only surprise of the morning at the Aquatics Centre, where Queen Elizabeth appeared briefly.

Olympic champion Park Tae-hwan of South Korea won his 400 freestyle heat, but was disqualified for a false start. Paul Biedermann of Germany, the world record holder in the event, failed to make the final.

"That's the Olympics," said Canadian Ryan Cochrane, who barely made the 400 free final. "It's always a surprise, every single heat. You just have to focus on your own race."

Phelps, the two-time defending Olympic champion, won his 400 IM preliminary heat in 4 minutes, 13.33 seconds with a time that was well off his world record of 4:03.84 set four years ago in Beijing, when Phelps won a record eight gold medals.

But it was only good enough to secure the last spot in the evening final, when Phelps will swim in Lane 8 instead of the middle of the pool.

"The only thing that matters is just getting a spot in," he said. "You can't win the gold medal from the morning."