Snyder is scheduled for back surgery on Friday. To take his place on the roster, Pittsburgh purchased the contract of Wyatt Toregas from Triple-A Indianapolis -- where he was hitting .034 (1-for-29).
Snyder left Wednesday's game after sliding awkwardly into second base trying to stretch a single during the second inning. Former starter Ryan Doumit (left ankle sprain) has been out since May 30, and the organization's No. 3 catcher, Jason Jaramillo, is on a minor league disabled list with an elbow injury.
For now, journeyman Dusty Brown (29 career at-bats) is the Pirates' starter, although manager Clint Hurdle said neither Brown nor fellow 28-year-old Toregas (51 career at-bats) would catch too many consecutive days.
Hurdle also indicated the team was pursuing catching options outside of the organization.