Roy Oswalt is retiring after 13 major league seasons.
The pitcher's agent, Bob Garber, confirmed the decision Tuesday and said the right-hander would go to work for his agency.
The 36-year-old Oswalt had a 163-102 career record with a 3.36 ERA. A three-time All-Star and the 2005 NL championship series MVP, Oswalt won 20 games in consecutive seasons (2004-05) with the Houston Astros. He pitched more than 200 innings seven times but was hampered by injuries in recent years.
Oswalt was 0-6 with an 8.63 ERA in nine outings and six starts for Colorado last year. He signed a minor league deal with the Rockies in May 2013 and missed time with a strained left hamstring.
A 23rd-round pick by Houston in the 1996 amateur draft, Oswalt pitched his first nine-plus seasons for the Astros and then played for Philadelphia, Texas and the Rockies.
AP Sports Writer Ronald Blum contributed to this report.
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