Middle-distance swimmer Kosuke Hagino, who won the 2016 Rio de Janeiro Olympics' men's 400-meter individual medley, announced his retirement on Sunday.

The 27-year-old Hagino won bronze in the same race at the 2012 London Games as a high school senior. He also won the 200 IM silver and a bronze in the 4x200 freestyle relay in Rio but failed to reach a podium this summer in Tokyo.

Japan's Kosuke Hagino (R) and Daiya Seto are pictured after swimming in the men's 200-meter individual medley final at the Tokyo Olympics on July 30, 2021, at Tokyo Aquatics Centre in the capital. (Kyodo)

Japanese swimmer Kosuke Hagino, the 2016 Rio de Janeiro Olympic gold medalist in the men's 400-meter individual medley, poses for photos after announcing his retirement at a press conference in Tokyo on Oct. 24, 2021. (Kyodo) ==Kyodo

"I'd decided that my last race would be at the Tokyo Olympics," Hagino told a Tokyo press conference. "I'm amazingly happy and have no regrets. When it came to bringing it to an end, I had a strong inner resolve."

Hagino was sixth in Tokyo in the 200 IM and failed to qualify for the final as a member of the 4x200 relay.

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