The Osaka District Court found Sho Darvish guilty of taking hundreds of bets on Major League Baseball and on professional baseball games in Japan last year.
The court said the 27-year-old younger brother of Yu Darvish was sentenced to two years and four months in prison, but the sentence was suspended for five years. The court said the defendant's gambling was limited to his group of friends and was not linked to organized crime, according to local media reports.
The younger Darvish took bets of 10,000 yen ($100) on Japanese and American professional baseball games, accepting wagers totaling about 110 million yen ($1.1 million) through the LINE social networking application, Kyodo News reported.
Sho Davsish himself bet roughly 220 million yen ($2.2 million) on the games, Kyodo said.
His arrest last year led to an investigation of Yu Darvish, but the authorities found no involvement by the Rangers star.
Sho Darvish reportedly said during his trial that he regretted causing trouble to his family and that he planned to change his surname to make their relationship less obvious.
But on Tuesday, Judge Hajime Hashimoto reportedly advised Darvish that what should change are his actions, not his name.