He was largely a starter over his first four years in the O's system, but was converted to a reliever in 2013 and his results seemed to improve at that point. In fact, as the AAA Norfolk Tides closer this season, he had 8 saves and a 0.96 ERA with 30 strikeouts over 18.2 innings in 16 appearances. Those are the kind of numbers that dignify a promotion!
Good luck with the Orioles Oliver! I have a feeling that you might stick around in Baltimore if you continue to pitch the way you have been so far!