Kanae Yamabe downed rival Megumi Tachimoto for her third national judo championship title on Sunday to clinch a spot in this summer's Rio de Janeiro Olympics.

In the pair's third meeting in the final at the national championships in as many years, and this year serving as the final qualifier for Rio in the over-78-kg category, holder Tachimoto injured her left knee with under a minute remaining.

Yamabe, who won the title in 2014, scored a wazaari before pinning Tachimoto to the mat for a second wazaari to secure an ippon victory as Tachimoto was stretched off at Yokohama cultural gymnasium.

"I was really frustrated to lose last year and I'm really glad to get the title this time," Yamabe said. "It was a battle against myself.

"I decided never to step back and give everything I had today. I just had my eyes on getting an ippon whatever I had to do."