Pop exited Thursday's game against the Red Sox with right hamstring discomfort, Keegan Matheson of MLB.com reports.
The Blue Jays said they will give Pop the night to rest and reevaluate him tomorrow. However, the injury appears to be a longer-term issue that will ultimately force him to the injured list. Pop has struggled early on this season, posting a 6.59 ERA across 13.2 innings.