Surprised nobody gave any updates on this.
He made his debut last Thursday. He pitched a scoreless inning, striking out one (the worst Molina) and walking one.
He also pitched an inning in the next game giving up an earned run on two hits and two walks.
He pitched the ninth inning in both games.
He was sent back down the next day.
http://www.baseball-reference.com/players/gl.cgi?id=geltzst01&t=p&year=2012