Eveland, traded to the Blue Jays by Oakland in the off-season, scattered five hits in his first start with Toronto (4-1). He walked two and struck out two.
"It was actually one of the weirdest games I've ever pitched," the left-hander told reporters. "I just had a good changeup (pitch).
"It was down in the zone and had a little sink to it and they (the Baltimore batters) were just beating it into the ground or popping it up."
Toronto catcher Jose Molina admitted that had prompted him to continue to call for the pitch.
"When you have a team that is chasing a pitch you just try to keep going with it until they show you that they can make the adjustment," Molina said.
"Tonight, the Orioles didn't make that adjustment on him, and that's why we took advantage of it."
Eveland, 26, had not been expected to make the five-man starting rotation for the Blue Jays, but an 1.80 earned run average in spring training helped keep him on the roster.
"We were going to give him a shot to see if he could become one of the starters," manager Cito Gaston said.
"If not, we thought maybe if he didn't pan out as far as a starter, we'd put him in the bullpen."
Molina figured in two of the Blue Jays runs. He was hit by Orioles starter David Hernandez with the bases loaded in the fourth to force in one run, then singled home Edwin Encarnacion in the sixth.
Designated hitter Adam Lind delivered Toronto's other run with an RBI double in the ninth.
(Reporting by Gene Cherry in Salvo, North Carolina; Editing by Greg Stutchbury)