Kevin Youkilis returned to the Red Sox lineup Tuesday night and gave Boston a lift with a fourth inning solo homer.
But Youkilis' shot was one of only two Boston hits on the night as the Orioles downed the Red Sox, 4-1.
Brian Matusz was dominant for the Orioles, working 6.1 innings while striking out nine.
Felix Doubront was solid for Boston, going 6 innings while giving up two earned runs on four hits. Matt Albers struggled in relief for Boston.