Koroibete produced a dominant performance as Saitama Panasonic Wild Knights outclassed Matt Toomu'a Mitsubishi Heavy Industries Sagamihara Dynaboars 61-29 in Tokyo on Sunday.

The imposing Fijian-born winger scored his fourth try of the season on the scoresheet as Saitama ran in nine tries to four to remain unbeaten in this year's competition.

Staring a total rout in the face as they trailed 49-8 at halftime, Sagamihara showed some spirit, 'winning' the second half 21-12, with former Wallaby centre Curtis Rona among their try-scorers.

Fellow former Wallaby Nick Phipps was a two-time try-scorer for NEC Green Rockets Tokatsu.

But the halfback's tries were in vain as Kobelco Kobe Steelers prevailed 59-26 to leave NEC stranded in 11th, and now almost certainly condemned to a place in the end of season relegation series.

Although Saitama appears unlikely to be caught in the race for the top qualifying position ahead of the May playoffs, Bernard Foley's Kubota Spears Funabashi Tokyo Bay took a big step towards securing a home semi-final by finishing second, after a crucial 15-5 win over fellow title-contender Yokohama Canon Eagles in Tokyo.

Kubota led 5-0 at halftime after the ninth try of the season by Springbok hooker Malcolm Marx.

With his countryman, second rower Ruan Botha, adding a second after halftime, the Spears pushed out to a 15-0 advantage before Canon scored their only points three minutes before the end.

The loss dropped Yokohama to fourth, just three points ahead of Toshiba Brave Lupus Tokyo, who survived a late rally by Toyota Verblitz to win 19-18, after Verblitz fullback Tiaan Falcon missed a conversion from a handy angle in the game's final act.

Australian fullback Sam Greene was the hero for the Shizuoka Blue Revs, scoring all 19 points as his side handed Ricoh Black Rams Tokyo their first defeat in four matches.

The 19-15 win lifted the Blue Revs out of the relegation zone.

Australian Associated Press