Alvarez will require surgery after being diagnosed with a torn UCL in his left thumb, Mike Puma of the New York Post reports.
Alvarez suffered the injury during Friday's game versus the Dodgers when he planted his left hand into the ground after stumbling on his turn toward second base. The catcher reportedly told teammates that he expected to miss 6-to-8 weeks, but a clearer timetable for his return could be available following the surgery. With Alvarez on the shelf, Omar Narvaez and Tomas Nido will handle the catching duties for the Mets.