US swimmer Michael Phelps looks on after competing in the men's 400m individual medley heats swimming event at the London 2012 Olympic Games in London. AFP/Martin Bureau
The two-time defending Olympic champion won his 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.
Kosuke Hagino of Japan led the way in 4:10.01. Chad le Clos of South Africa was second at 4:12.24. American Ryan Lochte advanced in third at 4:12.35.
Laszlo Cseh of Hungary, the silver medalist in Beijing, was ninth and missed the final by one spot.