Right-handed pitcher Mike Mussina, who collected his first 20-victory season last year in his 18th major-league season, has retired.

Mussina, 39, amassed a 270-153 record over a career that began with the Baltimore Orioles in 1991. He pitched for the Orioles for 10 seasons and the last eight for the New York Yankees before announcing Thursday he was retiring.

He was 20-9 in 2008 with a 3.37 earned run average, becoming the oldest pitcher to collect 20 wins in a season. He also was awarded his seventh Gold Glove for fielding excellence.

Mussina was credited with 2,813 strikeouts over his career, which is 19th on the all-time list. His winning percentage of .638 is sixth best among pitchers who have at least 500 career starts.

He walked 785 batters over 3,562 2/3 career innings, a rate of 1.98 walks every nine innings. Only two other pitchers -- Cy Young and Jack Quinn -- pitched at least 3,000 innings and walked an average of less than two batters every nine innings.

Mussina never won the Cy Young Award but finished at least sixth in the voting nine times. He was second in 1999 to Boston's Pedro Martinez and sixth this season.