Last Updated: 28/07/12 4:35pm
Fourteen-time Olympic champion Michael Phelps only just scraped into the final of the 400m individual medley as competition began in the pool at the Olympics.
Defending champion Phelps was the last qualifier for the final, setting only the eighth fastest time in the heats - four minutes 13.33 seconds - and making it through by just 0.07secs.
He said: "I didn't expect those guys to go that fast. I just wanted to try to get some good underwater, try to get some good times.
"A final spot is a final spot. I was slower this morning than I was four years ago, so I guess that's probably the only difference.
"I think the only thing that matters is really getting a spot in (the final). You can't win the gold medal from the morning.''
Phelps is bidding to become the most decorated Olympian in history at these Games - he currently had 16 medals, two fewer than Soviet gymnast Larisa Latynina.
Beijing silver medallist Laszlo Cseh and Britons Roberto Pavoni and Joe Roebuck also failed to make it through.
Pavoni, competing in the same heat as Phelps and Cseh, finished fourth in 4:15.56. Roebuck was seventh in his heat in 4:20.24.
Fastest through was Japanese swimmer Kosuke Hagino while world champion Ryan Lochte recorded the third best time although he was clearly easing down when caught by South Africa's Chad Le Clos.
Meanwhile, Fran Halsall was the first British woman to make it into the pool in heat four of the 100m butterfly.
She finished second in 58.23secs and eighth overall going into Saturday evening's semi-finals.
Ellen Gandy was also second in the following heat in 58.25, going through in ninth.
However, American Dana Vollmer made a statement of intent, the 2011 world champion setting a new Olympic record of 56.25.
David Carry became the first Briton to book a final spot when he qualified seventh overall in the 400m freestyle heats in a time of 3:47.25. However, Robbie Renwick failed to progress. He was 10th in 3:47.44.
Carry, the oldest member of the team at 30, said: "It's a dream come true, really, to be in a final of the Olympic Games.
There was a further shock as defending champion Park Tae Hwan disqualified for an apparent false start, but he was later reinstated after an appeal.
World record holder Paul Biedermann did fail to make it through though.
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