Holland, who tied for the National League lead with 41 saves last season for the Colorado Rockies, signed with the Cardinals just prior to the season on a one-year, $14 million contract.
He hasn't pitched since May 25 because of right hip impingement and struggled mightily before his injury with a 9.45 ERA in 13 1/3 innings pitched. He has blown his only two save opportunities this season and was removed from the closer's role in early May in favor of Bud Norris.
Holland hasn't fared any better in the minors, where he is 0-2 with a 6.43 ERA in seven innings pitched.
Bowman is 0-2 with a 5.75 ERA in 20 1/3 innings pitched this season.