Radhames Liz (3-0) got the win after giving up three runs on seven hits in six innings. The Orioles have won five of Liz's six starts since he was called up in early June.
Brian Roberts hit a solo homer for the Orioles. Brandon Fahey had a double and RBI in place of shortstop Alex Cintron, who was placed on the 15-day disabled list Tuesday with a strained left hamstring.
Luke Hochevar (5-6) gave up six runs on six hits in six innings for his first loss since May 29.
Alex Gordon had a double and home run, while Mark Teahen also homered and had two RBI for Kansas City.