CC Sabathia made it official on Monday, announcing on Twitter that he was retiring.

Sabathia, who said before the season that this year would be his last, posted a farewell letter to baseball on Twitter, two days after the Yankees’ season ended with a loss in Game 6 of the ALCS in Houston.

Any doubt Sabathia was finished was erased when he suffered a separated shoulder throwing a pitch in his final appearance in Game 4. The injury forced the Yankees to remove Sabathia from the roster, which meant he would have been inactive for the World Series if the Yankees had advanced.

Here’s how Sabathia said goodbye to the game after a 19-year career:

“It all started in Vallejo, CA in my grandma’s backyard throwing grapefruits at a folding chair. I could have never imagined how much this game has meant to me since. Through the ups and downs, baseball has always been my home. From Cleveland, to Milwaukee, to New York and everywhere in between, I’m so thankful to have experienced this journey with every teammate past and present. All I ever wanted to do was to be a great teammate and win. I’m so proud of this year’s team, we fought til the end. Love you guys! I’m going to miss going out there on the mound and competing , but it’s time to say farewell. Thank you, Baseball.”