That was one of a series of roster moves for the Cubs, who also activated right-hander Kyle Hendricks from the injured list, recalled reliever Randy Rosario from Triple-A and optioned reliever Rowan Wick to Triple-A.
Alzolay allowed seven runs, all earned, in 2 2/3 innings in the loss Monday. Alzolay did quality work in his first two appearances for the Cubs but heads back to Iowa with a 7.15 ERA. Manager Joe Maddon indicated earlier Tuesday that the 24-year-old Alzolay remains in the team's plans for the second half of the season.
"Of course," Maddon said on the Laurence Holmes Show. "We just haven't mapped it out all the way."
Hendricks had been on the injured list since June 15 with a shoulder impingement. He will start for Chicago at Pittsburgh on Tuesday night. He's 7-5 with a 3.36 ERA this season.
Rosario was a member of the Opening Day roster for the Cubs and joins the team for his third stint this year. He posted a 6.43 ERA in eight appearances in his previous stints. Rosario has a 2.25 ERA at Triple-A this season.
Wick had a 3.86 ERA in five relief appearances for the Cubs. He has a 2.22 ERA at Triple-A.