Ryota Murata, the first Japanese boxer to win both an Olympic and professional world championship, said Wednesday he has effectively retired.

Former WBA middleweight super champion Ryota Murata (C) of Japan is pictured after he was beaten by technical knockout in his title unification bout against IBF champion Gennadiy Golovkin of Kazakhstan at Saitama Super Arena on April 9, 2022. (Kyodo) ==Kyodo

The 37-year-old middleweight lost his WBA super world belt to IBF champion Gennadiy Golovkin of Kazakhstan last April in a ninth-round technical knockout in their title unification bout.

"Inside my head I'm thinking, 'that was my last,'" Murata said of the defeat. "I just haven't been able to announce it (until now), but that's how I'm thinking personally."

The Nara Prefecture native won silver at the 2011 world championships before seizing an Olympic gold medal in 2012, Japan's second in boxing and the country's first in 48 years.

After making his professional debut in August 2013, Murata won the WBA title in October 2017 against Hassan N'Dam of France in a seventh-round technical knockout.

The title came in a rematch five months after losing to the Frenchman, in a controversial decision that saw two judges suspended after ruling in N'Dam's favor.

Japanese boxer Ryota Murata slugs Hassan N'Dam of France in a WBA middleweight title fight at Ryogoku Kokugikan in Tokyo on Oct. 22, 2017. (Kyodo) ==Kyodo

Murata lost his second title defense a year later against Rob Brant but reclaimed the belt with a technical knockout of the American in their July 2019 rematch.

Murata ends his professional career with 16 wins, including 13 by knockout, and three defeats. His bout against Golovkin came after a two-year, four-month absence from the ring due to the pandemic.

He was 119-19 as an amateur.

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