CHICAGO -- The Chicago Cubs placed right-handed starter Keegan Thompson on the 15-day IL Saturday with low back tightness and recalled righty Anderson Espinoza from Triple-A Iowa.
The 27-year-old Thompson leads the Cubs in wins with a 9-5 record and 3.97 ERA in 25 games. He has made 17 starts since joining Chicago's rotation on May 11.
Manager David Ross doesn't believe Thompson's injury is serious, but said it affected the righty on Friday against Milwaukee when he allowed five runs - all from home runs - in 3 2/3 innings in a second straight shaky start.