Kensuke Tanaka hit a tiebreaking two-run single in the sixth inning, leading the Hokkaido Nippon Ham Fighters to a 4-2 win over the Tohoku Rakuten Golden Eagles on Friday.
The Fighters broke a third-place tie with the Chiba Lotte Marines in their bid to earn a Pacific League Climax Series berth.
In the day's only game, Tanaka singled up the middle off Hisashi Iwakuma (10-9) with the bases loaded and two outs in the sixth at Kleenex Stadium.
"I told myself in that situation we'll lose if we don't score in that inning," Tanaka said of his at-bat in the sixth. "Without thinking about my individual stats, I'll just try to help the team win all three remaining regular-season games. Our ace (Yu Darvish) is pitching tomorrow so we win and stay in third place no matter what."
The top three teams advance to the two-stage Climax Series.
Ryo Sakakibara (10-1) allowed one run in five innings in relief of starter Masao Kida. Hisashi Takeda earned his 19th save with a 1-2-3 ninth.
Atsunori Inaba singled in two runs in the third.
Iwakuma gave up four runs in six innings.
On Saturday, the front-running Fukuoka Softbank Hawks will clinch the PL title if they beat the Fighters and the second-place Seibu Lions lose to the Eagles.
