Japanese boxer Ginjiro Shigeoka has undergone brain surgery in the wake of his IBF world minimumweight title defeat, the Japan Boxing Commission said Tuesday, with the 25-year-old set to retire.Shigeoka was not knocked down during Saturday's 12-round split-decision loss to Filipino champion Pedro Taduran at Intex Osaka but began losing consciousness in the ring after the result was announced. He was stretchered out and rushed to a hospital.Under JBC rules, a boxer who has had brain surgery cannot hold a professional license, meaning Shigeoka must retire from the sport.Shigeoka is in an inte…READ FULL ARTICLE