TOKYO (AP) — Two-time double Olympic champion Kosuke Kitajima announced his retirement from competitive swimming on Sunday, two days after failing to qualify for the Rio de Janeiro Olympics.

Bidding to qualify for his fifth Olympics, the 33-year-old finished fifth in the men's 200-meters breaststroke at the national championships on Friday after barely missing out in the 100 earlier in the week.

"I knew the end was going to come sooner or later," Kitajima said. "I had to accept the fact that I wasn't going to the Olympics."

Kitajima hinted after Friday's race that he would retire and confirmed his intentions at a press conference in Tokyo on Sunday.

He won gold medals in the men's 100 and 200-meter breaststroke at both the Athens and the Beijing Summer Olympic games.

Kitajima is Japan's most decorated swimmer and also claimed a silver medal in the 4x100m relay at the London Olympics four years ago.

"I'm grateful for the career I had," Kitajima said. "I managed to win Olympic gold because of my coach and with all the support I had."