Y.A. was one tough little SOB, and a great competitor, but not as great of those already mentioned. On the other hand, if success is the real measure of a QB, then Otto Graham must be a top, if not the top, of all-time. For those not knowing, check out his career stats, wins, championships, etc.
Sammy Baugh was great as well and a two way player if I recall from NFL History pieces....