The Philadelphia Phillies are moving catching prospect Tommy Joseph to first base.

After suffering several concussions behind the plate, Joseph is officially being converted from catcher to first base. He began working out at the position on Saturday.

"He's not going to catch going forward," said Joe Jordan, the team's director of player development. "We're not going to expose him to that type of risk.

"Tommy is very excited about the move and anxious to get back on the field playing again."

Joseph, 23, is a former second-round pick of the San Francisco Giants. He joined the Phillies in the summer of 2012 as the centerpiece in the trade that sent Hunter Pence to the Giants.