Personal Catcher

From BR Bullpen

A personal catcher is a catcher who catches one pitcher in order to give the regular catcher a day off. This catcher rarely catches the other pitchers on the staff. A personal catcher is often used with a knuckleballer. The idea goes back to the 1930s, but it has become more prevalent in recent years.

There have been some extreme cases of a personal catcher.

In a rare case of a personal catcher associated with a relief pitcher, the Montreal Expos kept Tim Spehr on the roster from 1993 to 1996 to act as reliever Mel Rojas's personal catcher. Rojas threw a nasty forkball that few catchers could handle.