The Cincinnati Reds placed left-hander Nick Lodolo on the 15-day injured list Tuesday with a blister on his left hand.
The move is retroactive to Monday.
"It was a big deal he was able to pitch with that," Reds manager David Bell told reporters. "The good thing is it's not broken open. We just got to be sure it doesn't turn into something bigger than that."
Lodolo, 26, is 8-3 with a 2.96 ERA in 12 starts. He has struck out 73 batters in 70 innings.
Lodolo is 14-11 with a 3.86 ERA in 38 career starts over three seasons with Cincinnati.
Also on Tuesday, the Reds recalled right-hander Yosver Zulueta from Triple-A Louisville.
Zulueta, 26, is 2-0 with a 2.93 ERA in 23 relief appearances with the Bats. He has yet to make his major league debut.