Whether Allen wins the center job or is a backup again, I'm sure he has been prepared to play at least two spots on the line. He wouldn't have been a game-day backup last year otherwise. At Michigan State he started 16 games at LG, 17 at C and 5 at RG.
Saffold started out as a RT with the Rams in 2010- until he was a LT. And then a RG. And then a LG. They'll prepare Allen and I'm sure he will either start or be their primary interior OL backup.
