Let's not forget the running games and defenses those two quarterbacks have had.  Roethlisberger had Bettis to start his career and a really good defense to relieve pressure.

 

Manning had Tiki Barber, and everyone knows about their defense.

 

Bortles has had little to no run game, a poor offensive line, and although last years defense was decent, the year before they were awful.

 

Bortles isn't perfect, but a semi balanced offense will really help.

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