Tsumura cleared to ride Realize Sirius in Japanese Derby despite injury

Akahide Tsumura stayed aboard Realize Sirius after a pre-race injury, and that clearance reshaped the 93rd Tokyo Yushun before the field even reached the gate. The Japanese Derby ran May 31, 2026 at Tokyo Racecourse, 2,400 meters on turf, with total prize money of ¥651,000,000 and ¥300,000,000 to the winner, making every small edge matter in a race that has defined three-year-old excellence since 1932.

Realize Sirius entered as one of the leading contenders after finishing second in the Satsuki Sho, and the colt’s final major workout at Miho Training Center pointed to a horse holding his form. Working solo over the woodchip track on May 27, he covered six furlongs in 84.1 seconds, with splits of 37.5 and 11.3 seconds, a sharp enough effort to support the view that he remained in good shape despite the late scare around his rider.

For Tsumura, the ride carried both history and pressure. It was his fourth Japanese Derby appearance, and his best finish before this year was 10th aboard Bitter Ender in 2020. He had partnered Realize Sirius throughout the colt’s development, which made the assignment more personal and more consequential: the rider who knew the horse best also had to prove he could deliver under classic-race pressure after an injury that briefly put the pairing in doubt.

Trainer Takahisa Tezuka said Tsumura’s feedback had been important because Realize Sirius had become a little more tense, and the team adjusted the final preparation accordingly. That detail mattered as much as the clearance itself. In a Derby field built on stamina and composure, a horse that tightens up can lose the decisive rhythm at Tokyo Racecourse, especially over 2,400 meters on turf where position, timing and trust between rider and colt often decide whether a contender becomes a champion or just another near miss.

Tezuka also carried added stakes of his own, with multiple Derby chances and a shot at his first classic sweep. Against that backdrop, Tsumura’s recovery from injury did more than keep a mount in the race. It preserved one of the more compelling upset angles in the Derby, a rider-horse combination now defined as much by resilience as by talent.