I know I will be beat up and told this is far too simplistic of an explanation, etc., but I feel there is weight to it: They drafted BB because they thought he was the next Big Ben. 

That was the label entering the draft, but unfortunately for Jag fans, there is a LOT more to being another Ben as roughly sharing the same size as him. 

I remember I was at Sneaker's Sports Grill in Jax Beach during that draft, and when the Jags picked Bortles, I said it then and there, "That's a terrible pick." 

There is so much more to what makes Ben good then his size. More than anything it's his intangibles, which Blake has none of. 

Also, Ben has a nice, clean throwing motion compared to Blake's bizarre corkscrew throwing motion, which gives defenders a full half second extra to know where he is throwing, which, 
in the NFL is an eternity. (Leftwich had a similar problem with telegraphing where he was throwing - albeit a different screwed up throwing motion). 

Ben is far from perfect (as we saw in both games vs. Jags last season) but he is better than most QBs out there and is a "winner." He can (not always) find a way to win in
less than ideal circumstances. Blake will never be a QB like that. And he will never attain Ben's level of play. I know I maybe stating the obvious now, but I never thought
Blake would ever come close to providing the play of Big Ben. 

Jags got to find a QB in order to advance. Where they can find one will be explored in another thread.

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