Chinese heavyweight Sun Yang battered his rivals to create history Monday as the swimming goliath scooped the first-ever Asian Games men's 800 metres freestyle gold with another monstrous performance.

Greeted like a rock star with high-pitched squeals from an excitable section of female Chinese fans in Jakarta, the triple Olympic champion claimed a runaway victory in a new Games record of seven minutes, 48.36 seconds.

Sun, who blazed to the 200m title at the weekend, uncoiled his rippling two-metre frame to pull away over the second half of the race to leave Japan's Shogo Takeda and Vietnam's Nguyen Huy Hoang flailing in his wake.

"I was saving some energy for tonight's relay," growled Sun, who returns later in the men's 4x200m freestyle relay."The plan was to pick up the pace over the last 200 metres and it went well. That will give me confidence for the 2020 Tokyo Olympics."

China topped the medals on day one on Sunday, winning four golds to Japan's three, led by their talismanic team captain.

Elsewhere, Japanese Olympic gold Rikako Ikee won her second and third gold medals of the competition in the 50m butterfly and 100m freestyle.

The 18-year-old, who lit up the recent Pan Pacific swimming championships in Tokyo, is expected to be a force in the 100m free and 100m fly at the 2020 Olympics in her home city.

Ikee breezed to victory in Monday's one-lap race in a Games-best 25.55 -- almost half a second clear of China's Wang Yichun.

After setting a new competition best in the 100m free in helping Japan win the weekend's 4x100m free, Ikee returned for swimming's blue-riband event to duck under that record again, winning in 53.27 from China's Zhu Menghui (53.56). Japan teammate Kosuke Hagino will also be favourite to retain his title in the 200m individual medley later on Monday.

Other Swimming medals:

Swimming Men's 200m Individual Medley 

Swimming Women's 100m Freestyle 

Swimming Women's 200m Breaststroke 

Swimming Men's 4 x 200m Freestyle Relay