The Cubs had optioned Ramirez to Triple-A Iowa on Saturday and recalled right-handed pitcher Blake Parker.
"He was sore the day after and the right thing to do was to put him on the DL," Cubs general manager Jed Hoyer said Tuesday. "He's going to be fine, he'll be back right when the DL stint ends, or we assume that."
Ramirez has pitched 28 innings in relief this season, leading all Cubs relievers with an 0.96 ERA. The 25-year-old rookie was acquired last season in a trade that sent starting pitcher Matt Garza to the Texas Rangers.