Four Division World Champion Kosei Tanaka Announces His Retirement

In a shocking announcement to those outside of his inner circle, 29-year-old former WBO super flyweight champion Kosei Tanaka has announced his retirement from the sport of boxing.

The former four-division champion, who holds the record for reaching that achievement faster than any fighter in the history of the sport, is hanging up the gloves due to some serious eye issues that will see him never having 100% vision for the rest of his life.

In an Instagram post from his verified account, Tanaka (20-2, 11 KOs) detailed the reasons why he decided the time was now, which did not appear to be easy, according to the things he said within the post.

“Thank you so much for all your support over the years. The reason is all about my repeated eye injuries. The last defense match took place on 14 October (2024). The condition of both eyes was bad before the fight, and I decided to have surgery on both eyes immediately after the fight.

“However, immediately after the start of the match, I lost sight in my right eye, and by the third round, all the light had completely disappeared. With my left eye also in a bad state, I finished the match and underwent surgery on both eyes.”

“My vision was restored, but even now, my right eye’s vision is still heavily distorted, and I can no longer focus with both eyes. Due to the effects of hernia operations on my neck and many, many operations on my eyes alone in the four years from 2021, my eyes have become weak, and I can no longer spar, let alone compete.