Jon Lester announced his retirement from MLB Wednesday, bringing his 16-year run to an end.

The 38-year-old is a three-time World Series champion and was one of three active players with 200 career wins (Justin Verlander and Zack Greinke).

MLB LOCKOUT TALKS TO RESUME AFTER MONTH BREAK: SOURCE

After making 30 or more starts 12 times during his career, Lester goes out on his own terms.

"It’s kind of run its course," Lester said, via ESPN. "It’s getting harder for me physically. The little things that come up throughout the year turned into bigger things that hinder your performance.

Jon Lester #31 of the St. Louis Cardinals looks on during the game against the New York Mets at Citi Field on September 15, 2021 in New York City. The Cardinals defeated the Mets 11-4. 

Jon Lester #31 of the St. Louis Cardinals looks on during the game against the New York Mets at Citi Field on September 15, 2021 in New York City. The Cardinals defeated the Mets 11-4.  (Getty Images)

"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."

While Lester spent time with the Athletics (2014), Nationals and Cardinals (2021), he’ll forever be known for his stints with the Red Sox (2006-14) and the Cubs (2015-20).

Selected by Boston in the second round of the 2002 MLB Amateur Draft, Lester went 110-63 with a 3.64 ERA and 1,386 K’s. Lester was the ace of the 2013 World Series team, pitching to a 0.59 ERA in two starts against the Cardinals.

CLICK HERE FOR MORE SPORTS COVERAGE ON FOXNEWS.COM

His career year, however, came in 2016, when the Cubs broke the curse and won their first World Series since 1908. Lester pitched to a career-low 2.44 ERA that season and was named the NLCS MVP.

Jon Lester #31 of the St. Louis Cardinals throws a pitch against the Milwaukee Brewers at American Family Field on September 20, 2021 in Milwaukee, Wisconsin. Cardinals defeated the Brewers 5-2. 

Jon Lester #31 of the St. Louis Cardinals throws a pitch against the Milwaukee Brewers at American Family Field on September 20, 2021 in Milwaukee, Wisconsin. Cardinals defeated the Brewers 5-2.  (Photo by John Fisher/Getty Images)

"I remember the nervous feeling I had before Game 4 of the World Series in 2007," Lester said. "I remember standing on the mound in Game 5 against St. Louis in 2013, in a tie series, and an [paper] airplane got thrown from the upper deck that lands right behind the mound. I still remember looking at that.

"And then the turmoil of Game 7 in 2016 [when the Cubs won in extra innings]."

Lester is undoubtedly one of the best left-handed pitchers of all-time, one of nine in the modern era to win 200 games and have a career ERA under 4.00. Per ESPN, six of the other eight are in the MLB Hall of Fame.

Perhaps his most inspiring moment came in 2007, when Lester was diagnosed with anaplastic large T-cell lymphoma. With his immediate MLB future in doubt, Lester underwent chemotherapy and was able to return in the same season.

CLICK HERE TO GET THE FOX NEWS APP

Jon Lester #34 of the Washington Nationals pitches against the San Francisco Giants in the bottom of the first inning at Oracle Park on July 10, 2021 in San Francisco, California. 

Jon Lester #34 of the Washington Nationals pitches against the San Francisco Giants in the bottom of the first inning at Oracle Park on July 10, 2021 in San Francisco, California.  (Photo by Thearon W. Henderson/Getty Images)

"I was in Triple-A on a rehab assignment in Pawtucket after cancer," Lester said. "My parents were there and they were leaving that day or the next day to go home, and I told them they have to change their flight and I said, ‘I’m starting the next night in Cleveland.’

"That’s one of the top moments of my career. Seeing their faces was pretty cool. Once I got back to baseball, I tried not to take anything for granted and really appreciated being around the guys."