?Park Tae-hwan of the Republic of Korea celebrates after winning gold in the men's 100m freestyle final in the swimming event on Wednesday. Peter Parks / Agence France-Presse

The Republic of Korea's (ROK) superstar Park Tae-hwan won the men's 100m freestyle on Wednesday to make it a sensational Asian Games triple gold after victories in the 200m and 400m events.

The 400m freestyle Olympic champion's bid for his third title in Guangzhou was in deep trouble when he made the turn in fifth place but he stormed back to beat China's Lu Zhiwu for his fifth medal of the Games.

Elsewhere on the penultimate night of action, China's Tang Yi won her fourth gold and sixth medal overall, taking the women's 100m freestyle.

China won 22 gold medals out of a possible 32 in the pool, with Japan picking up six and the ROK four, but the host nation didn't have it all its own way as Park seized the limelight again.

He clocked 48.70sec in beating Lu by 0.28sec, with Japan's Takuro Fujii third.

"I am so happy to get the gold medal in the 100m freestyle after winning the 400m freestyle last night because the 100m is not my main event," said Park.

"I didn't even think about getting a medal before the race. I just wanted to be in the final because the Chinese and Japanese competitors are very strong.

"Before the race I just wanted to swim as fast as I could. In the first lap I was in fifth place and I felt nervous. After turning, the wave was so strong and that made it difficult to swim," the 21-year-old added.

"In this Asian Games I have broken my personal bests in the 200m and 400m freestyle."

Park won three gold, a silver and three bronze medals at the 2006 Asian Games in Doha - the biggest medal haul by a single athlete.

Tang's 100m freestyle gold was one of three won by China on Wednesday and comes on top of wins by the 17-year-old in the 4x100m freestyle relay, 4x100m medley relay and 4x200m freestyle relay.

Tang, who clocked 54.12sec in beating compatriot Li Zhesi and Japan's Haruka Ueda, has won silvers in the 50m and 200m freestyle events.

"It was not easy to get this medal tonight. I felt nervous. You can see from the women's 4x100m freestyle relay that the other competitors are very strong," Tang said.

"I wanted to go faster tonight but maybe I didn't because I swam in too many races at the Games and am short of energy."

Zhao Jing took the women's 100m backstroke in 59.20sec after her earlier win in the 200m event. Shiho Sakai of Japan won silver and China's Gao Chang the bronze.

But Zhao was disappointed with her time, saying: "I could have swum faster but my condition is not so great. If I gave myself a score it would be 95 (out of 100). I can do better."

China's Li Xuanxu, 16, won the women's 800m freestyle in 8:23.55 ahead of compatriot Shao Yiwen, 15, and Japan's Maiko Fujino.

There was more success for the ROK when a tearful Jeong Da-rae won gold in the women's 200m breaststroke in 2:25.02, edging Chinese pair Sun Ye and Ji Liping.

Japan's Ken Takakuwa claimed the men's 200m individual medley with China's Wang Shun second and Japan's Yuya Horihata third.

Meanwhile, four-time Olympic champion Kosuke Kitajima was forced out of Thursday's 200m breaststroke with shoulder pain.

Kitajima took gold in the 100m and 200m breaststroke at the 2004 Olympics and retained both titles in Beijing.

But his plans for a third consecutive Asiad double have badly gone awry.

He finished fourth in Tuesday's 100m, following his fourth-place in the 50m.