4. Ben Roethlisberger, Pittsburgh Steelers
Big Ben can still sling it—maybe better than he ever has, with a gaudy completion percentage of 68.0 and 328.2 passing yards per game (both career highs) last season. But his superb 8.4 yards per pass in 2015 was somewhat offset by the reality that he only started 11 games due to an assortment of injuries to his shoulder, knee and foot. That was the fewest starts of his 12-year career, and the Steelers need him for something closer to 16 games if they want to harbor legitimate Super Bowl dreams this year. Roethlisberger still takes a ton of punishment in the pocket, but last year he started to pay the price for all that pounding and big-play potential. With so much skill-player talent surrounding him, the goal in Pittsburgh has to be keeping Roethlisberger upright.