Teruaki Sato homered for the second straight game as the Hanshin Tigers beat the Yomiuri Giants 4-3 to clinch their first Central League title in 18 years and sixth overall on Thursday.
The Tigers, unbeaten so far in September, completed a three-game sweep of the archrival Giants at Koshien Stadium while extending their winning streak to a season-high 11 games.
"I'm glad we won the title today in front of Tigers fans at Koshien because we are going to Hiroshima tomorrow," Hanshin manager Akinobu Okada said.
The Tigers and the second-place Hiroshima Carp are scheduled to play a two-game series from Friday at Mazda Stadium.
"I repeatedly told my players that September would be the month of a real battle, but we've won way more than expected."
Yusuke Oyama hit a sacrifice fly for the game's first run, and Sato followed with a two-run blast over the center-field wall for a 3-0 lead in the sixth inning.
Hanshin starter Hiroto Saiki (8-5) allowed one run and three hits in seven innings for the win.
Kazuma Okamoto hit his Japanese baseball-leading 39th home run of the season for the Giants, a solo shot in the seventh. Yuji Akahoshi (3-5) took the loss.
In other action, the DeNA BayStars defeated the Chunichi Dragons 8-3, while the Seibu Lions beat the Fukuoka SoftBank Hawks 4-2.