Seth Wenig/Associated Press

New York Yankees pitcher CC Sabathia formally announced his MLB retirement in a tweet Monday.

Sabathia, 39, previously announced the 2019 season would be his last in February. He went 5-8 with a 4.95 ERA and 1.41 WHIP during the regular season and did not give up a run in two relief appearances during the Yankees' ALCS loss to the Houston Astros.

The lefty's career ended after he suffered a shoulder subluxation (dislocated shoulder) during his Game 4 relief appearance. It was a disappointing ending to a season mired with injuries—first a knee ailment that kept him on the shelf in the spring and then shoulder problems that cropped up in the home stretch.

"In a way, it is kind of a perfect way [to leave]. We talk about him being the greatest teammate and this person we all revere so much," Yankees manager Aaron Boone told reporters. "He left it all out there. He gave us everything he had. Even though it is sad to see him walking out, but there is something kind of awesome to it in a weird way too."

Sabathia ends his career as a six-time All-Star, 2007 AL Cy Young winner and member of the Yankees' 2009 World Series championship team. He's one of only three left-handers in history with 3,000 strikeouts, and his 251 wins ranked as the highest among active pitchers and pitchers whose career began after the year 2000.

The biggest knock against Sabathia making the Hall of Fame is his career 3.74 ERA, which would tie for the third-highest by a player to reach Cooperstown. Working in Sabathia's favor: Jack Morris (3.90 ERA) and Mike Mussina (3.68 ERA) have reached the Hall in recent years. His numbers also look stronger when adjusted for era, even if he's far from a slam-dunk candidate.

Sabathia began his career with the Cleveland Indians in 2001 and remained with the franchise until a 2008 trade to the Milwaukee Brewers, which was one of the most impactful July deals since the turn of the century. He helped push the Brewers to their first postseason berth since 1982 and finished sixth in NL MVP voting despite playing only half the season in that league.

The Yankees came calling with a massive contract the following winter, and Sabathia spent his final 11 seasons alternating between ace and source of consternation in New York. His legacy is ultimately one of being a great teammate and one of the best pitchers of his generation—regardless of whether he ultimately hits the Hall of Fame threshold.