O'Brien 2-for-4 with his third home run of the season and three RBI on Saturday for Triple-A Reno. The slugger has a .375/.390/.700 batting line so far for Arizona's AAA affiliate. He continues to work in the outfield, but the club has indicated he will get back behind the plate at some point. O'Brien continues to show off the power that is his calling card, but he has yet to draw a walk through 41 plate appearances this season, which suggests he has some work left to do in his development as a hitter.