Japan's 2004 Olympic hammer-throw winner Koji Murofushi confirmed his retirement during a visit to the Japan Sports Agency on Friday, two weeks after he missed out on a place in the Rio de Janeiro Olympics.

The 41-year-old returned to the national championships following a two-year absence, seeking his 21st title and his fifth consecutive Olympic berth, but the bronze-medal winner in London four years ago fell short at Paloma Mizuho Stadium. He settled for 12th on 64.74 meters and said he was leaving the front line.

"I'm retiring from top-level competition, but will now concentrate on contributing to the Japanese sporting world," said Murofushi, the Japanese national record holder (84.86 meters).

He is currently the sports director for the 2020 Tokyo organizing committee.

"The medals will shine even more depending on how you live your life after retirement, " said JSA Commissioner Daichi Suzuki, the former gold-medal winner in the 100-meter backstroke at the 1988 Seoul Games. "I hope he'll set an example for his fellow juniors."

Murofushi hopes watching his past performances will impact other athletes just like Suzuki's influenced him.

"(Suzuki) was a good reference during my career as an athlete. It'll be great if my throws lead to someone's gold medal," Murofushi said.