Glasnow was recalled from Triple-A Indianapolis on Tuesday.
With Indy's season drawing to a close Monday, Glasnow will return for the final month of the major league season. Glasnow struggled in a pair of starts for the Pirates earlier this year before a shoulder issue put him on the shelf, and he's not scheduled to start a game for Pittsburgh in the immediate future. He will likely serve as the long man out of the bullpen, at least for the time being.