The American League Cy Young Award winner last season, Bieber struck out three and threw 34 pitches in a 1-0 loss to the Chicago White Sox on Friday night. Cleveland interim manager DeMarlo Hale said before the game that Bieber would be on a pitch count. He threw 57 pitches in a minor league rehab game Sunday.
Bieber, who made it clear during his lengthy rehab that he wanted to return this season, is 7-4 with a 3.17 ERA in 15 starts. He went 8-1 with a 1.63 ERA in 12 starts during the shortened 2020 season.
In other team news, shortstop Amed Rosario was activated from the COVID-19 list. He had previously been on the bereavement list and missed additional time because of health and safety protocols.
The Indians optioned infielder Ernie Clement, left-hander Francisco Perez and right-hander J.C. Mejia to Triple-A Columbus. Right-hander Nick Sandlin (sore shoulder) was transferred to the 60-day injured list.
The Associated Press contributed to this report.