Warren (nose) began a minor-league rehab assignment with Triple-A Salt Lake on Friday and threw a scoreless inning, Rhett Bollinger of MLB.com reports.
Warren was hit in the face by a batted ball during batting practice May 3 and was diagnosed with a broken nose. He underwent surgery a week later and took some time to recover before making his return to the mound Friday. He'll likely need a few more rehab outings before he's ready to return to the big-league club.