Bieber (elbow) threw off a mound Saturday, Anthony Castrovince of MLB.com reports.

Bieber (elbow) is scheduled to begin throwing off a mound in mid-February.

Bieber said Wednesday that he has been throwing from 90 feet three times per week, Tom Withers of the Associated Press reports.

Bieber (elbow) agreed to terms on a contract with the Guardians on Friday, Buster Olney of ESPN reports.

Bieber underwent Tommy John surgery on his right elbow Friday, Tom Withers of the Associated Press reports.

The Guardians transferred Bieber (elbow) to the 60-day injured list from the 15-day IL on Wednesday.

The Guardians placed Bieber (elbow) on the 15-day injured list Saturday.

Bieber will undergo season-ending Tommy John surgery, Tom Withers of the Associated Press reports.

Bieber (2-0) picked up the win Tuesday against the Mariners, allowing six hits over six scoreless inning. He struck out nine and did not issue a walk.

The Guardians announced Tuesday that Bieber will start Opening Day against the A's on March 28, Tom Withers of the Associated Press reports.