As Michael Lewis' "The Blind Side" clearly explained, the left tackle position has now become the second most important position on the field and his thesis is no more evident than with what the 2012 Denver Broncos are facing.

Peyton Manning never missed a start before the 2011 season. His only documented missed snaps resulting from an injury are the ones following a busted open lip against the Miami Dolphins in the early 2000's. Manning personified the iron man mentality that we all want from our quarterbacks. Unlike Favre with all of his consecutive starts, Manning was never even on the Colts' weekly injury reports.

That all changed last off-season. Following a series of neck surgeries, Manning sat out all of last season and watched his Colts miss the playoffs for the first time in 10 years. There is no defined time for when his injury occurred. Rumors swirled about when the first sign of his neck injury may have happened throughout the 2010 season. All of a sudden though, the consistent sight of No. 18 leading the Colts to yet another playoff appearance was gone and in his place were quarterbacks hanging on to the fringes of a career.

Flash forward to the 2012 off-season. Manning gets released from the Colts and after weeks of positioning themselves, the Broncos won the Peyton sweepstakes and the services of arguably the best quarterback of his generation. All that stand between them and another season in the playoff hunt are Manning and his health.

Since being drafted in the first round of the 2008 draft, Ryan Clady has been amongst the top left tackles in the NFL. His two Pro Bowl and All-Pro selections show the consistency he's had for during his career. And he's done all of this without ever missing a start.

It's no secret that the Broncos are nervous about Manning's health. How could they not be? Despite not being an expert neurologist, it seems to me that any potential hit to Manning's neck could be the one that ends his season, and maybe his career.

Clady has been steady for the entirety of his NFL years and there is no better time than now to have his best season. Manning may have the great ability to sense pass rushers and get rid of the ball before being swallowed up by them, but that will not stop James Harrison, John Abraham, and Terrell Suggs from bearing down on him as often as possible.

For any investment to pay off there must be some security to provide assurance. Clady is just that for Manning, and the season is just as dependent on him, as it is for 18.

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