DENVER – The Colorado Rockies made a roster move involving their bullpen on Sunday. Veteran reliever Chad Qualls has been placed on the 10-day disabled list with back spasms. Taking his spot will be the yo-yo-ed right hander Carlos Estevez.

Qualls is in his second season with Colorado and will be making his second journey to the disabled list this season. He’s struggled with injuries in his tenure in Denver.

In the past week Qualls has thrown just three pitches. On the year, he has a 1-0 record and a 4.60 ERA in 17 appearances.

Estevez has pitched in almost as many big league games this year—16—as Qualls. The flame throwing 24-year-old was briefly Colorado’s closer last year. In 2017 he has a 3-0 record with an 8.16 ERA. He’s also appeared in 13 games for Triple-A Albuquerque where he has a 2.92 ERA.