Chicago Cubs right-hander Trevor Williams was placed on the 10-day injured list Monday with appendicitis.
The move was made retroactive to Friday.
The Cubs recalled right-hander Kohl Stewart from Triple-A Iowa in a corresponding move and he will start Chicago's game on Monday against the San Diego Padres.
The 29-year-old Williams is 3-2 with a 5.36 ERA in 10 starts this season.