The Rangers selected Wynns' contract from Triple-A Round Rock on Tuesday, Jeff Wilson of AllDLLS.com reports.
With Kyle Higashioka (forearm) landing on the injured list Tuesday, the Rangers will turn to Wynns to bolster their depth behind the plate. The 35-year-old backstop has just four hits in 53 big-league at-bats this season, but he's slashed .289/.413/.474 at Triple-A since signing a minor-league deal with Texas in late June. He'll presumably serve as the backup to Elias Diaz while Higashioka and Danny Jansen (forearm) are on the shelf.