NTT Communications Shining Arcs kept alive their hopes of a top-four finish in Group A and a spot in the playoffs to determine the Top League champions on Saturday with a 29-15 win over Honda Heat.
Head coach Rob Penney's decision to keep a number of his senior players on the bench eventually paid dividends as NTT's replacements scored three second-half tries at Prince Chichibu Memorial Ground.
"It was a frustrating game on a number of levels but I am really pleased with the result," Penney said.
Five teams in Group A are still in contention for a spot in the playoffs and Saturday's result sets up a do-or-die clash for NTT next week against Kintetsu Liners, who are currently third, two points behind Comms but with a game in hand.
The top four in Group B, meanwhile, have already been determined and all four sides were in action Saturday as they battled it out to determine the final seedings for the playoffs.
Yamaha Jubilo with newly appointed "Master of Ninja" Ayumu Goromaru at fullback went into the weekend in the top spot. But Goromaru and his teammates showed little fighting spirit as they suffered their first loss of the season.
Yoshikazu Ohashi scored four tries as Kobe Kobelco Steelers beat last year's Top League runners-up 43-14 to go top of the standings with 25 points.
Canon Eagles trail Kobe on points difference after they topped Toyota Verblitz 26-10, with Yamaha third on 24 and Verblitz fourth on 21.
Meanwhile at the other end of the table, NEC Green Rockets picked up their first win of the season by beating winless Coca-Cola Red Sparks 20-12.