Alfredo Despaigne hit a three-run homer in the eighth inning as Cuba beat two-time defending champions Japan 6-3 to finish first in Group A of the World Baseball Classic on Wednesday.
Despaigne's home run off reliever Takeru Imamura at Fukuoka Dome put the game out of reach and allowed Cuba to set up a second-round showdown with Group B runner-up the Netherlands on Friday.
Yasmany Tomas hit a solo homer to left in the bottom of the third to give Cuba a 1-0 lead. Frederich Cepeda doubled in another run in the fourth and Jose Abreu made it 3-0 on a single to left in the sixth that scored Luis Rivera from third.
Japan, who scored three runs in the ninth, will face Group B winner Taiwan in the second round at Tokyo Dome.
Japan continue to struggle for offence without their top players from Major League Baseball. The three runs in the ninth were more a result of poor pitching by Cuba's relievers, who issued three walks in the final inning.
Cuba, who routed China 12-0 on Monday, continued to display the type of offensive power that makes the 2006 runner-up a title contender this year.
The win was Cuba's first in four WBC games against Japan.
Cuba starter Wilber Perez picked up the win after holding Japan scoreless over three innings. Japan starter Kenji Otonari gave up one run on two hits in three innings to take the loss.