The St. Louis Cardinals placed left-hander Matthew Liberatore on the 15-day injured list Tuesday with tightness in his lower back.
The Cardinals called up right-hander Jacob Barnes from Triple-A Memphis in a corresponding transaction.
Liberatore, whose designation is retroactive to Saturday, is 2-5 with a 6.12 ERA in 50 innings over 12 games (11 starts) this season. He had been scheduled to start Wednesday's series finale at Pittsburgh.
Barnes, who has not pitched in the majors in 2023, signed with St. Louis last month after being released by both the Philadelphia Phillies and Texas Rangers this season. He is 0-1 with a 1.53 ERA in 11 relief appearances at Memphis.
Barnes, 33, is 8-16 with a 4.70 ERA and seven saves in 252 games (one start) with seven teams since making his major league debut with the Milwaukee Brewers in 2016.