Dan Haren will retire at the end of the season.
Haren won his final regular season game and isn't likely to end up on the postseason roster for the Chicago Cubs.
His ERA in August was 6.31, but it was just 2.36 in September.
"Happy the way the last few starts have gone," Haren said. "Being able to contribute to this amazing team. I'm just thankful to be a part of it."