SoftBank Hawks right-hander Kazumi Saito signed Saturday with the Pacific League club for three years.
His contract is worth an estimated 750 million yen plus performance-based incentives.
Saito's annual salary expands to 250 million yen from his current 150 million yen, making him the highest-paid pitcher in club history.
He was 16-1 with a 2.92 ERA in 22 games this year after matching a Japanese record with a 15-0 start to a season.