Allen is expected to be called up from Triple-A Columbus to start Tuesday against the Pirates, Mandy Bell of MLB.com reports.
With Shane Bieber (forearm) likely joining Cal Quantrill and Triston McKenzie on the injured list, Allen should have a secure rotation spot for the foreseeable future. The young southpaw had a 4.76 ERA, 1.68 WHIP and 20 strikeouts in 22.2 innings over his five most recent MLB starts.