; born July 15, 1982) is a Korean professional baseball relief pitcher for the Toronto Blue Jays of Major League Baseball (MLB).
He previously played for the Samsung Lions of the KBO League in South Korea, the Hanshin Tigers of Nippon Professional Baseball (NPB) in Japan, and the St. He is known as "Dol-bucheo" (Stone Buddha) for being unshaken and maintaining an emotionless face in every situation.
He is considered to be one of the greatest closers in the history of Korean baseball.
His prowess as a relief pitcher also earned him the nickname, "Kkeut-pan Wang" (Final Boss), in South Korea and among Cardinal fans.
Oh attended Kyunggi High School in Seoul, South Korea.
He had been a pitcher since he began baseball, but he switched to the outfield after getting serious arm injuries in 1999.
In 2004, his senior year at Dankook University, Oh won most of the Korean college pitching awards.In June, Oh made his first appearance for the South Korea national baseball team at the 2004 World University Baseball Championship held in Tainan, Taiwan.He led his team to the bronze medal, playing most of the games in closer duty.The Samsung Lions selected Oh in the second round (5th pick, 12th overall) of the 2005 KBO First Year Players draft.After signing with the club, he contributed a strong rookie season as a setup man and closer in 2005, going 10–1 with a 1.18 ERA, 16 saves (sixth in the league) and 115 strikeouts (fifth in the league) in 99 innings pitched over 61 games.