The NL Central leaders made the announcement before Tuesday night’s game at Arizona.
Morrow, who tops the Cubs with 22 saves, has been on the disabled list since July 19. The Cubs are without their two relievers with the most saves — Pedro Strop has 13 and is out with a hamstring injury, and the team hopes he’s ready for the post-season.
The Cubs will go with a closer-by-committee plan going forward. Morrow, who posted a 1.47 ERA in 35 games, is expected to be ready for spring training in 2019.