Japan finished the opening night of the Asian Games swimming competition on Sunday with three gold medals, a confidence-boosting effort with the 2020 Tokyo Olympics less than two years away.

Olympic medalists Satomi Suzuki and Daiya Seto prevailed in the women's 100-meter breaststroke and the men's 200 butterfly, respectively, while the Japanese women's team led by Rikako Ikee won the 4x100 freestyle relay at the games for the first time since 1994, and in a national record time.

Ryosuke Irie saw his hopes of a third successive Asian Games gold dashed, having to settle for second behind reigning world champion Xu Jiayu of China in the men's 100-meter backstroke final at the GBK Aquatic Center.

The veteran Suzuki, who won three medals at the 2012 London Olympics, clocked 1:06.40 seconds, a new games record, giving Japan its first gold medal of the multi-sport games that run through Sept. 2 in Indonesia.

"My form was good...After passing 75 meters, it was hard but I swam like mad," the 27-year-old told reporters. "The win has given me confidence looking ahead to the Tokyo Olympics."

(Satomi Suzuki)

Suzuki's compatriot Reona Aoki touched in second at 1:06.45 and China's Shi Jinglin in third almost a second behind the gold medalist.

Seto, winner of the 200 butterfly bronze at last year's worlds, utilized a late surge to finish top with a 1:54.53-second time, ahead of compatriot Nao Horomura and China's Li Zhuhao.

"The time was faster than I thought," said Seto, who earlier in the day said he was aiming for a time in the 1-minute, 53-second range.

Japan then finished the evening on a high with the women's team winning the 4x100 freestyle relay in 3:36.52, 0.26 ahead of China. Japan's win ended a run of five consecutive golds in the event for China.

"By winning gold in the first race, I have established a good flow for myself and for the Japanese team," the 18-year-old Ikee said. "I have two events tomorrow so I'd like another gold."

(Japan's 4x100m freestyle relay team)

The Japanese delegation sees the Asian Games in Indonesia as a valuable proving ground for the 2020 Tokyo Olympics, where it aims to win 30 gold medals.

In the men's 100 backstroke, Irie could only manage a 52.53-second swim, not enough to top Xu who clocked 52.34 for gold, a time that equaled the games record set by Irie at the Incheon Asian Games in 2014.

"I am frustrated, but a loss is a loss. I want to reset and aim for the gold in the 200 (backstroke)," Irie said.

Among other events on swimming's opening night, Japan's Katsuhiro Matsumoto settled for silver with a time of 1:46.50 in the men's 200 freestyle as Rio gold medalist Sun Yang of China dominated.

In the women's 1,500 freestyle, held for the first time at the Asian Games as it will be at the Olympics in 2020, Japan's Waka Kobori took bronze behind China's Wang Jianjiahe and silver medalist Li Bingjie.

In the women's 200 backstroke Natsumi Sakai finished second behind China's Liu Yaxin.