Are Ryan Tannehill's Days as Starter for the Dolphins Numbered?

It has been said before that the most popular player on most football teams is the backup quarterback. The clipboard-holding bastion of hope provides even the worst of NFL franchises something to look forward to, and something to overhype while he stands on the sideline doing nothing.

Lately, this has become true in Miami, where 2012 first-round pick Ryan Tannehill is falling out of favor quickly despite a change in offensive coaching this summer that should have improved his game and helped the Dolphins take the next step and contend in 2014.

But is Ryan Tannehill really in trouble? Is it time for the Dolphins to move on?

Sliding Downhill

Heading into his third season in the NFL, there was hope that Tannehill would take yet another step forward. He improved from Year 1 to Year 2, playing with more efficiency and control and earning better metrics according to our Net Expected Points (NEP) data.

But as you can see in the table above, he's backtracked in nearly every way this season, nearly matching his cumulative negative grade from 2012 on a fraction of the snaps. He's the fourth-worst quarterback this season according to our data, with Chad Henne and Josh McCown among the few worse than him.

Let's put this into a bit more historical context to show just how bad of a start Tannehill is off to. Since 2010, among quarterbacks to drop back to pass more than 100 times, the Miami passer ranks in the 13th percentile at -.13 NEP per drop back. The only current starters who have posted a season that poor over the past three seasons are E.J. Manuel, Geno Smith and Kirk Cousins.

His rookie season ranks in the 30th percentile of quarterback seasons since 2010, and his 2013 campaign finished in the 41st percentile.

It's All Downhill From Here

The biggest problem with all of this data is that it flies in the face of what logically should have happened this season. Tannehill and the Dolphins transitioned to the Bill Lazor offense in 2014, who was the quarterbacks coach for a previously struggling Nick Foles in 2013.

Foles rebounded from a -13.38 NEP rookie season to post a 108.68 NEP in his second year under center, with Kelly and Lazor's offense largely receiving the credit. Foles has continued to play well for the Eagles, but in Miami, Tannehill is having the worst year of his career in what should be a more forward-thinking offense.

But should we have seen this coming? Our JJ Zachariason wrote an article this summer warning that Tannehill may be in trouble, as his NEP over his first seasons in the NFL didn't bode well for his future when compared to historical examples in our data. Drew Brees, Matthew Stafford and Alex Smith are the only three quarterbacks to amount to anything to have a lower Total NEP during their first two campaigns.

Brees rebounded in heroic fashion in his third season, posting a .30 NEP per drop back, an improvement of nearly half a point per opportunity compared to his previous season. Tannehill is obviously not on a similar course, and won't become the next Drew Brees.

Stafford didn't make quite the same leap as Brees, but did come back after an injury-shortened season to post career highs in every metric we have, highs that still remain after two more seasons for the Detroit signal-caller. So again, there are no signs pointing to a Stafford-like career path for Tannehill.

Alex Smith, on the other hand, did continue to struggle, eventually getting phased out of the starting job in his third and fourth seasons before re-emerging later on in his career under better coaches and with better weapons.

The other quarterbacks with similarly humble starts to their careers read like a front office blooper reel: Sanchez, Kolb, McCoy, Ramsey, Losman.

Time to Make a Change?

So what's the verdict for the Dolphins? Is it time to bench Ryan Tannehill, and allow him to go the way of Alex Smith, sitting on a bench and hoping to finally "get it" enough to become an average NFL quarterback?

That's a decision the Dolphins should wait to make until after the season at the earliest, as Tannehill provides the best chance to win right now for a team that has a good enough defense (fifth according to our metrics) to compete in a weak AFC East.

Matt Moore is the only other quarterback on the roster in Miami, and despite posting a slightly better career average NEP per drop back than Tannehill (-.02 as compared to -.03), he is one of the quarterbacks lower than his competitor on both the "worst seasons since 2010" and "worst first two seasons for a starting quarterback" lists referenced above.

The highs for Moore might be higher, but the lows are much lower, including a 2010 campaign that ranks 11th worst (5th percentile) since that season. He has no future, either, and putting him in to play quarterback is a lateral move (at best) that leaves the Dolphins with even less film and data to make a decision on Tannehill's future this upcoming offseason.

But a lack of legitimate competition in Miami is the only reason why Tannehill should continue to hold his job uncontested. He needs to have a Nick Foles-like turnaround under Lazor in a hurry, or else he'll slowly go the way of Vince Young, Colt McCoy, and the other failed young quarterbacks who faded away into spot-starting duty and eventual obscurity. There will almost certainly be a change under center in Miami this offseason, barring a miraculous turnaround for the incumbent.