Former world champion Ginjiro Shigeoka has had to undergo brain surgery after collapsing in the ring following his IBF strawweight title defeat to Pedro Taduran last weekend.

Kumamoto, Japan's Shiegoka's fight with Taduran was their second duel, having fought each other last summer in a bruising encounter which ended in a 9th-round stoppage win for the Filipino.

Taduran won the IBF 105-pound title that night at the Shiga Daihatsu Arena in Otsu, while Shigeoka collapsed post-fight and needed surgery on an orbital fracture.

Shigeoka, 25, was given the all-clear to return to action and went straight back into a rematch with Taduran, who won their sequel via split decision at the Inter Osaka on May 24.

In yet more distressing scenes, however, Shigeoka collapsed once again, but this time he was unresponsive and had to be stretchered out of the ring before being rushed to hospital.

No-one connected to the event had been able to provide an update on Shigeoka's condition until now. Viva Promotions, who promote Taduran, have been told by the Japanese Boxing Commission (JBC) that Shigeoka has had brain surgery.

As a result, the JBC have enforced Shigeoka's retirement from boxing.

The update read: “According to JBC [Japanese Boxing Commission], Japanese Former IBF Champion Ginjiro Shigeoka has suffered from an acute subdural hematoma and has already undergone a craniotomy.

“G. Shigeoka is still currently under observation in a private hospital in Osaka, Japan. The commission has already enforced that Shigeoka has to retire from boxing following his craniotomy procedure.”

A craniotomy is a seriously delicate surgery to undertake as it involves removing a portion of the skull in order to gain access to the brain which, in Shigeoka's case, has suffered a bleed.

Shigeoka remains unconscious and hospitalised following his surgery.