LONDON China's Sun Yang posted the fastest time in the heats of the men's 1500 metres freestyle on Friday to stay on course to complete the long-distance double at the London Olympics.
Sun won the 400 gold medal on the opening day of competition at the Aquatics Centre and is the overwhelming favorite to win the 1500, the longest and most grueling race in the pool, after setting the world record at last year's world championships in Shanghai.
Churning through the water with seemingly effortless ease, Sun won his heat in a time of 14 minutes, 43.25 seconds, well outside his world record but nearly more than three seconds faster than anyone else.
Tunisia's Oussama Mellouli, the defending Olympic champion, was second fastest overall, ahead of Canada's Ryan Cochrane and Italy's Gregorio Paltrinieri.
"I had some problems with my shoulder bugging me for the last three years but it seems to be working pretty well this morning," Mellouli said.
"I woke up mentally not 100 per cent. The race went well, I'm feeling pretty confident for tomorrow."
South Korea's Park Tae-hwan, silver medalist in the 400, qualified sixth as 10 men broke the magical 15-minute barrier.
"I am happy with my time but it's slower than my PB," said Park. "It was an average race."
Sun has been one of the outstanding swimmers in London, winning silver medals in the 200 freestyle and 4x200 relays, in addition to his gold in the 400.
Just six men have completed the Olympic 400-1500 double with Russia's Vladimir Salnikov the last to achieve the feat, 32 years ago, in 1980.
(Reporting by Julian Linden; Editing by Greg Stutchbury)