Alvarez was released by the Tigers on Thursday, Evan Woodbery of MLive.com reports.

Alvarez (elbow) signed a minor-league contract with the Tigers on Friday.

Alvarez (elbow) underwent Tommy John surgery Wednesday, Maria I. Guardado of MLB.com reports.

Alvarez recently suffered a setback in his rehab program from his left elbow injury and is expected to undergo Tommy John surgery, Susan Slusser of the San Francisco Chronicle reports.

Alvarez (elbow) threw a bullpen session Friday, Evan Webeck of The San Jose Mercury News reports.

Alvarez (elbow) began a throwing progression Friday, Maria I. Guardado of MLB.com reports.

Alvarez (elbow) received cortisone injection Thursday and hopes to avoid surgery, Susan Slusser of the San Francisco Chronicle reports.

Alvarez will not undergo surgery on his left elbow for the time being,Susan Slusser of the San Francisco Chronicle reports.

Alvarez (elbow) was transferred to the 60-day injured list Thursday, Amy Gutierrez of the Giants' official site reports.