RHP Tommy Hunter will pitch one inning for Double-A Bowie on Sept. 1 to stay fresh. He then can return to the Orioles on Sept. 3 ... Mychal Givens, who batted .243 in 100 games at Low-A Delmarva, is expected to be converted from an infielder to a pitcher this offseason. Givens was the Orioles' second-round pick in 2009. ... The Orioles will call up several players when rosters expand Saturday. One will be a third catcher — likely Luis Exposito, who is on the 40-man roster. ... Wilson Betemit (right wrist) came through his first rehab game at Double-A Bowie with no issues. He was hitless in four at-bats and was scheduled to play for the Baysox again Thursday night. He's expected to be activated by the Orioles this week. ... The Orioles can also expand their coaching staff in September. Former Orioles pitcher Scott McGregor will be with the club and travel with it for the remainder of the season. Triple A-Norfolk manager Ron Johnson and pitching coach Mike Griffin will join the Orioles on Sept. 11. Until then, roving instructors Dan Werner and Bobby Dickerson will meet the team in Toronto and throw batting practice. They will leave the club to begin the organization's Instructional League on Sept. 12 in Sarasota, Fla.. Minor league coordinator Brian Graham also may help out before he goes to Instructional League. ... Showalter said the condition of Nick Johnson's injured right wrist has not improved and he not expected to rejoin the Orioles this season.