I think he did, but what I remember is when most of the Washington RB's were hurt and he played RB.....and played it really, really well, I remember him having at least a few 100 yard games and he was a very good receiver out of the backfield, they used to use him as a part time 3rd down back as well.....
You're thinking of the infamous "Body Bag" game in 1990 vs. Buddy Ryan's Eagles where both the Redskins starting QB and back-ups were knocked out of the game.