The Cubs claimed Zastryzny (elbow) off waivers from the Brewers on Monday, Maddie Lee of the Chicago Sun-Times reports.

Zastryzny (elbow) was transferred to the 60-day injured list Thursday.

Zastryzny (elbow) began a rehab assignment with Triple-A Nashville on Friday, striking out a batter while allowing two walks and one hit over a scoreless inning in his first appearance.

The Brewers placed Zastryzny on the 15-day injured list Friday due to left elbow tendinitis, retroactive to Thursday.

Zastryzny will serve as the Brewers' opening pitcher for Wednesday's game against the Cubs, Adam McCalvy of MLB.com reports.

Zastryzny will serve as the Brewers' opening pitcher for Sunday's game against the Nationals, Todd Rosiak of the Milwaukee Journal Sentinel reports.

Zastryzny will serve as the Rockies' opening pitcher in Monday's game in Colorado.

The Brewers selected Zastryzny's contract from Triple-A Nashville on Saturday.

Milwaukee signed Zastryzny to a minor-league contract Tuesday with an invitation to major-league spring training, Adam McCalvy of MLB.com reports.

Zastryzny was designated for assignment by the Pirates on Monday.