- Bats Left, Throws Right
- Height 6' 1", Weight 187 lb.
- High School Taejon High School
- Debut April 4, 2005
- Final Game August 20, 2005
- Born August 2, 1968 in Daejeon, South Korea
A star in the Korea Baseball Organization (he was MVP in 1996 when he won 18 and posted a 1.88 ERA), Dae-Sung Koo signed with the Orix Blue Wave in Japan in 2001. He was 24-38 with 10 saves and a 3.88 ERA in four years with Orix; he topped a 4 ERA all but one year (5-7, 2.52, 2nd in the Pacific League in ERA) as he was mediocre in Nippon Pro Baseball. Many fans of Japanese baseball were amazed that any Major League team would be interested in a player who had been an average or worse pitcher in three of the prior four seasons.
Koo was in the 1989 Intercontinental Cup and starred in the 1991 Intercontinental Cup, going 3-0 with only 6 hits and one run allowed in 23 1/3 IP, fanning 31. He led the tourney in strikeouts, tied for the most wins and was second in ERA to make the tournament All-Star team as one of two pitchers (Omar Ajete was the other). He represented South Korea in the Olympics in 1992 and 2000 - in 2000 he beat Japan in the bronze medal game, allowing one run and five hits in 9 innings while whiffing 11 to beat Daisuke Matsuzaka.
After his one season in the US major leagues with the New York Mets in 2005, Koo returned to the KBO, signing with his former club, the Hanwha Eagles, for $550,000. In his first MLB at bat, Koo stood outside of the batter's box and did not swing the bat. In his second at bat, against Randy Johnson, Koo doubled and then scored on a bunt by Jose Reyes.