Glasnow will pitch in relief Wednesday before rejoining the Pirates' rotation, Stephen J. Nesbitt of the Pittsburgh Post-Gazette reports.
Glasnow struggled in his return to the rotation last week, so the club will temporarily shift him to a bullpen role before sending him back out for another start. It sounds like he'll be the first man used in relief following starter Steven Brault. He's expected to be reinserted into the rotation following Wednesday's appearance, though it's unclear when his next start will come.