Torii Hunter Hunter hit two home runs and 3, in the opener of a three-game series.
Peter Bourjos had three hits including a solo shot and Mike Trout, who was called up prior to the game, added a homer. The Halos have won two straight following a five-game skid.
Dan Haren (13-6) allowed three runs on nine hits while striking out eight over seven innings to earn the win.
Jo Jo Reyes (6-10) allowed five runs on eight hits over five frames to suffer the loss. He walked three and struck out six.
Adam Jones had a pair of RBI for the Orioles, losers of three straight and six of eight.