The Orioles placed another starting pitcher on the injured list.

After dealing with lower back discomfort during his last start, right-hander Chris Bassitt was placed on the 15-day injured list. The Orioles recalled right-hander Trey Gibson, who will start Monday’s series opener against the Mariners.

Gibson, a rookie, has started two previous games. In three appearances, he has a 3.65 ERA.

Bassitt dealt with lower back discomfort last week during his start at Fenway Park. He allowed three runs in three innings before departing. He flew to Baltimore for a doctor’s appointment and, upon returning to the team in Toronto, he reviewed opinions on his back. The result is a trip to the injured list.

Baltimore has three other starting pitchers on the shelf: right-handers Zach Eflin and Dean Kremer and left-hander Cade Povich.