Since 1901, there have been 201 instances where a pitcher has lost 20 games or more in a single season. The most recent pitcher to suffer this dubious “honor” was Mike Maroth in 2003, who went 9-21 for the Detroit Tigers ballclub that lost 119 games, one loss shy of the modern record for most losses in a season by one club. Before that, you have to go back to Brian Kingman, who lost 20 games with the Oakland Athletics in 1980.
In the team’s 106-year history, the Boston Red Sox have had exactly ten 20-game losers. The last time it happened, in 1930, the team actually had two 20-game losers in the rotation: Milt Gaston, who led the team with 13 wins against 20 losses, and Jack Russell, who posted a record of 9-20. That club also lost 102 games, the fourth time in six seasons that the club had lost 100 games or more. Gaston and Russell were also two of five pitchers that had lost 20 games or more over the previous six seasons; Red Ruffing, a future Hall of Fame pitcher whose career would blossom after being traded to New York in 1930, lost 25 and 22 games in 1928 and 1929, respectively; Slim Harriss lost 21 games againt 14 wins in 1927; and Howard Ehmke went 9-20 in 1925.
The four other pitchers in Red Sox history to lose 20 games in a season were: “Sad Sam” Jones, in 1919, two years before he would win a career-high 23 games while still with Boston; Joe Harris, who won just two games while collecting 21 losses in 1906; the legendary Cy Young, who lost 21 games in 1906, the third time in his career that he had lost 20 games or more in a season; and Bill Dinneen, who matched his 21 losses with 21 wins in 1902. Dinnenn was also the only pitcher to lose 20 games for a Boston club that had a winning record.