If we keep Fox as the backup catcher, then we can't use him as a pinch hitter. If we use him as a pinch hitter in, say, the seventh inning and then Hill is injured in the eighth - who catches? how likely is it that this happens? think about how specific the scenario you're describing is. fox pinch hits AND hill is injured afterwards to the point that he has to leave the game AND the game is close enough that an inning or two of fontenot or whatever catching makes the difference it's very unlikely we'd lose a game as a result of this. No matter how likely or unlikely it is, a manager generally won't do it. Lou has used pitchers to pinch hit before he's used backup catchers - even when we had one of the better hitting backups out there (Blanco). Whether those of us on here like it or not, if Fox is the only other catcher on the roster, his pinch hit chances would very likely decrease. Plus, having a guy like Fox bounce around between multiple different positions might make his already sketchy defense that much worse. He's already the backup third baseman and has gotten some time in the outfield (though that will be decreased significantly with Reed back). Generally if you have a guy who struggles defensively, you want to put him somewhere and let him focus totally on that position. You don't plug him into the most important defensive position on the field and then bounce him between it and third.