Former Red Sox and Cubs ace Jon Lester is retiring from MLB after a 16-year career, he told ESPN Wednesday.
Lester, 38, won 200 games throughout his career, and he retires as one of just nine modern left-handed pitchers with 200 wins, a .600 winning percentage and a career ERA under 4.00 per ESPN.
"It's kind of run its course," Lester said Wednesday. "It's getting harder for me physically. The little things that come up throughout the year turned into bigger things that hinder your performance.
"I'd like to think I'm a halfway decent self-evaluator. I don't want someone else telling me I can't do this anymore. I want to be able to hand my jersey over and say, 'Thank you, it's been fun.' That's probably the biggest deciding factor."
Lester was drafted by the Red Sox in the second round of the 2002 draft. Toward the end of his debut season with the Red Sox in 2006, he was diagnosed with anaplastic large T-cell lymphoma and underwent chemotherapy that offseason. Lester returned to the team midway through the 2007 season pitched for Boston from then until midway through the 2014 season, when he was traded to the Athletics.
That following offseason, he signed with the Cubs. He was named an All-Star twice throughout his tenure in Chicago, which ran until 2020.
Among his standout seasons with the franchise, in his second year with the Cubs, Lester went 19—5 with a 2.44 ERA. In the postseason that fall, he was named NLCS co-MVP and pitched three times in the World Series against Cleveland en route to winning a third World Series ring.
Lester began last season with the Nationals, but he was moved at the trade deadline and later made 12 starts with the Cardinals.