The Pirates recalled Sanders from Triple-A Indianapolis on Wednesday.
Sanders has given up just two earned runs while striking out 19 batters in 10 innings since being sent down to Triple-A at the end of May. He'll now return to the majors to give the Pirates' bullpen a fresh arm, though he'll likely be limited to low-leverage situations given that he's surrendered six runs in six innings with Pittsburgh. Brandan Bidois was optioned to Indianapolis in a corresponding move.