Imagine the worst possible quarterback to bury behind Joe Montana until he's 30. He's probably heavily reliant on athleticism; he has a lot of unique skills that could be maximized in an offense you build around them; he's a huge name who's already had a heavily publicized failure or two hung around his neck. He's really not like Sam Bradford-a conventional, highly talented, still popular face-of-the-franchise-at all. But he's Steve Young, and when he finally did hit the NFL full-time at 30 he had one of the most extraordinary statistical runs in football history.
Steve Young's early career is pockmarked by false starts—it began with an enormous contract that he had no chance of seeing the end of in the struggling USFL, and it continued in Tampa Bay, where he went 3-16 as the beleaguered Buccaneers' starter until they decided to replace him with the immortal Vinny Testaverde. In four seasons after that he put together a patchwork series of excellent performances before Joe Montana's injuries finally gave him a chance to start, whereupon he proved even better than anyone could have anticipated.
Football careers are strange, speaking as someone who's come from baseball's more easily understood Hall of Fame debates. Not every quarterback has so consistently confusing and second-chancey a career as Steve Young's, or Kurt Warner's, but Sam Bradford's doesn't much stick out yet.
For a complete look at SB Nation St. Louis's series on Sam Bradford and Hall of Fame quarterbacks who had similarly disastrous starts, click through to this Storystream and subscribe.