Jake Arrieta struck out five over four scoreless innings, allowing two hits in the Baltimore Orioles' 4-3 loss to the Pittsburgh Pirates on Monday.
Arrieta, the Orioles' opening-day starter last year, is competing for a job as the team's fifth starter. Left-hander Zach Britton, another of the candidates, allowed one run in two innings of relief, giving up an RBI double to Josh Harrison in the seventh.
Pirates left-hander Jeff Locke, also competing for a rotation job, gave up two runs and eight hits in 3 1-3 innings.
Baltimore's L.J. Hoes hit a two-out, RBI single in the second, and Lew Ford homered in the third.
Brad Hawpe, who played for Pirates manager Clint Hurdle in Colorado and is in camp as a non-roster invitee, homered in the eighth against Daniel Schlereth.