Irvin (shoulder) was placed on the 15-day injured list Thursday, Matt Kawahara of the San Francisco Chronicle reports.
Irvin has been dealing with shoulder soreness, and while no further diagnosis has been announced, he'll be out until at least mid-May. He delivered strong results early in the campaign, maintaining a 2.93 ERA and 1.16 WHIP across 27.2 innings. The team has not officially named a starter for Friday's game against the Twins to replace Irvin, though Zach Logue is the leading candidate.