RIZIN flyweight Sho Sekihara is in critical condition in a Chiba hospital after suffering an acute subdural hematoma in his loss to Takumi Hamada at RIZIN 55, according to a statement from the promotion. Sekihara, 33, was rushed into surgery the night of the fight, came through it, and then took a sudden turn the next morning that sent him back into the operating room.
“He lost consciousness due to an acute subdural hematoma and underwent emergency surgery at the Chiba Emergency Medical Center near the venue,” the statement read, as translated from Japanese by MMA Mania. “The surgery was completed, and he managed to survive, but his condition suddenly deteriorated the following morning, requiring another operation. His condition remains critical, and his prognosis is still uncertain.”
The finish came late. Sekihara had been getting tagged on the feet through the fight, per viewers on r/MMA, and in the final seconds of Round 3 at LaLa arena TOKYO-BAY, Hamada lifted him and drove him into the canvas on the back of his head. Punches followed (roughly 10 unanswered shots, by one fan’s count) before the referee waved it off with four seconds left on the clock. Sekihara left on a stretcher.
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The first word that something was badly wrong backstage came from the X account samaroont, which posted on November 11 that Sekihara had been forced into life-threatening brain surgery shortly after he was taken back for medical checks, adding that they had held off on posting publicly because of how serious it was.
The history everyone was already talking about
This is the second time Sekihara has been here. Four years ago, in 2022, he suffered a subdural hematoma that nearly ended his life and his career. He came back anyway, and he came back changed, abandoning the striking-heavy style he’d built his name on and rebuilding himself as a grappler. According to MMA Mania, he still carried a reputation for absorbing a lot of damage in his fights. The RIZIN 55 broadcast team brought up that first brain bleed before the opening bell, which is a hard detail to sit with now.
Support has started trickling in from the Japanese fight scene. Veteran Yusuke Yachi posted a short message on X, “関原くんがんばれ,” telling Sekihara to keep fighting.
The incident lands on a country already under scrutiny for brain injuries in combat sports. In 2025, two boxers on the same Japanese card died from brain injuries, which prompted calls for reform. MMA Mania raised the obvious question directly: whether Sekihara should have been medically cleared to compete again after 2022.
There’s no next fight to talk about here, and there shouldn’t be. The only update that matters is the next one from Chiba Emergency Medical Center. But someone, at some point, signed off on a man with a prior subdural hematoma walking back into a cage, and Sekihara rebuilt his entire style to make that comeback work. He did his part. RIZIN and whoever handled his clearance owe the public an explanation of how that decision got made, and they owe it now, while he’s still fighting for his life.
