Tatsuya Oishi

Tatsuya Oishi (大石 達也)

• Bats Left, Throws Right
• Height 6' 0", Weight 202 lb.
• School Waseda University
• High School Fukuoka University Ohori High School

• Born October 10, 1988 in Dazaifu, Fukuoka Japan

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Biographical Information

Tatsuya Oishui was a pitcher in Nippon Pro Baseball for 9 seasons, including 7 at the top level with the Seibu Lions of the Pacific League from 2012 to 2019. His first professional season in 2011 was spent entirely with Seibu's ni-gun squad in the Eastern League, as was the entirety of his 2014 season.

He was a major star in college at Waseda University where he played on the collegiate version of the Japanese national team that took part in the 2010 World University Championship and was named the relief pitcher on the tournament All-Star team as Japan won the Bronze Medal. Scouts at the tournament said that his fastball was of major league quality. He was the most sought-after player in 2010 NPB draft, being picked by six of the twelve teams, with Seibu winning his bargaining rights. It was a tremendous draft for Waseda, as two moundmates, Yuki Saito and Yuya Fukui, were also picked in the first round, the first time this had ever happened. He had been a position player in high school, and was known as an outstanding defensive outfielder before switching to the mound in college, after Waseda had originally recruited him as a shortstop.

For all the hoopla about his amateur career, his professional one turned out to be a huge disappointment. His first minor league season in 2011 was excellent, as he went 6-4, 2.25 in 15 games, but he never managed to find his footing at the top level, winning a grand total of 5 games (against 6 losses) in his seven seasons. He was used exclusively as a reliever, but only had 8 saves in 132 appearance. He did post some excellent ERAs over short stints - 2.74 in 24 games as a rookie in 2012, 1.71 in 36 games in 2016, and 0.93 in 20 games in 2017 - but when he was given a chance to be the team's top reliever in 2013, he failed miserably. He posted all 8 of his career saves that season, but overall was 0-5, 6.38 in 37 games. The closer's job went to Dennis Sarfate, and he was back in the minors full-time the next season. Recurrent shoulder issues that cost him a number of mph on his fastball were largely to blame for his lack of success at the top level. He also had some control issues: for example, he set the NPB record with 3 wild pitches in one inning in a 2016 appearance. He retired after the 2019 season as he had been advised that Seibu would release him.

He went into coaching after retiring as a player. In 2020, thanks to a partnership between Seibu and the New York Mets, he was supposed to serve as an assistant pitching coach with the St. Lucie Mets of the Florida State League, but the COVID-19 pandemic cancelled those plans. He then joined Seibu's minor league coaching staff.