Orioles rookie Kevin Gausman made his major-league debut Thursday night at Toronto.
Gausman, the fourth overall pick in the 2012 draft, struck out three through his first two innings and did not surrender a run until the fourth.
He allowed an RBI double to J.P. Arencibia and a sacrifice fly in the fourth. He then gave up a two-run home run to Arencibia in the fifth. The right-hander was charged with four runs and seven hits over five innings as he took the loss. He struck out five and walked two on 89 pitches.
Gausman, who went 2-4 with a 3.11 ERA at Double-A, is scheduled to start Tuesday at Washington.