Should the Buffalo Bills consider trading Kiko Alonso?

UPDATE: Three weeks after this post was written, the Bills traded Kiko Alonso to the Eagles for LeSean McCoy.

Every so often, starting as early as the midway point of the 2014 regular season, a brave soul following the Buffalo Bills has carefully tested the waters of whether or not the team could trade Kiko Alonso this offseason. (Heck, it just happened here yesterday.) Each time I have seen the idea broached, it's been met with typical Internet scoffing, all-caps indignation, and blatant dismissal.

Folks, it's really not that crazy. It's probably not going to happen - for a few very important reasons, which we will get to below - but GM Doug Whaley and the Bills' decision-making brass would be wise to shop one of their every-down linebackers via trade this spring. Here's why.

Personnel usage

We can talk until we're blue in the face about the differences between the defensive schemes employed by Rex Ryan and Jim Schwartz - and there are many, most of which are stylistic or fairly subtle - but the biggest functional difference is personnel usage. Ryan's defense uses different players in key spots.

What you see below is a comparison between the Ryan defense - employed in Buffalo by Mike Pettine during the 2013 season - and the Schwartz defense, purely from a group personnel usage standpoint. The biggest difference is glaring, but we'll start with the similarities. All of the figures below were cultivated from the team's snap count data from the past two seasons.

• DB usage: Ryan (43.5% of snaps), Schwartz (42.5%)

A lot has been made about how frequently Ryan's defenses in New York used defensive backs in bulk, but the fact of the matter is that no matter what scheme or style you're running on defense in today's NFL, you're using a ton of defensive backs. There are subtle differences between the two - Pettine used a lot of safeties, where Schwartz was more corner-reliant - but ultimately, there isn't much difference here.

• Edge defender (DE/OLB) usage: Ryan (18.3%), Schwartz (18.6%)

We're going to talk a lot about how Jerry Hughes fits back into Ryan's defense over the next several weeks, considering he was a part-timer under Pettine. That's a more nuanced discussion than is necessary here, though, because both of these systems used edge defenders roughly the same amount. Those players were just asked to do slightly different things from time to time.

Those are the points of similarity. The disparity comes when you start talking about defensive linemen and linebackers.

• DL usage: Ryan (23.7%), Schwartz (17.4%)

Based on a 12,000-snap season on defense (an average of about 68 plays per game), the difference between Ryan and Schwartz on the defensive line equals one, 750-snap (roughly) role. Alan Branch was the biggest contributor to that role under Pettine.

• LB usage: Ryan (14.4%), Schwartz (21.5%)

Those snaps that an extra defensive lineman were taking under Pettine had to come from somewhere, and that somewhere was the linebacker position. Again, based on a 12,000-snap season on defense, the difference between the two systems at this position is roughly one 850-snap role.

Basically, in terms of big-picture personnel usage, the Ryan defense takes a linebacker off the field, and puts a defensive lineman on it, on a significant portion of its plays. You probably knew that before you clicked on this article to read it; now you can quantify it. It's worth pointing out, though, that the disparity may not actually be as big as those numbers indicate, as Pettine's linebacker personnel was not as developed as Schwartz's. Still, the difference is very noticeable: the Bills will be using two linebackers a lot next year, as opposed to the three they used a lot last year.

Performance

Obviously, Alonso missed the entirety of the 2014 season recovering from a knee injury. That left Preston Brown, Nigel Bradham, and Brandon Spikes (a pending free agent) to handle the majority of the linebacker reps for Schwartz. Let's take a look at those four players' Pro Football Focus ratings - Alonso from 2013, the other three from last season - to compare them overall.

There is an issue of sample size with Spikes; he played less than half (46.4%) of the Bills' defensive snaps last season, and there's no question that had he been exposed to more snaps in nickel and dime looks, his coverage grade would be significantly lower. For Alonso, Brown, and Bradham - all of whom exceeded 800 snaps in their respective seasons - the grades are much more accurate.

In back-to-back years, Alonso and Brown held all-down roles as rookies for the Bills, with the only differences being that Alonso was much better in coverage (which is saying a lot, as Brown was excellent), and Brown was slightly better against the run. These two youngsters should be considered the top two players on Ryan's depth chart.

Again, Spikes is a pending free agent, and without a third linebacker role to fill, he'll probably explore greener pastures elsewhere. Bradham remains under contract, however, and unless something changes with Alonso and Brown, he might be the player that is marginalized under Ryan.

Why trading Alonso doesn't make sense

For the most part, the nascent idea of trading Alonso exists because of the success of Brown and Bradham last year (particularly against the run, where Alonso struggled for stretches in 2013), because of the pending scheme change, and because Alonso would conceivably yield the biggest return in a trade. Here are three reasons why it doesn't make sense to trade him:

• Accrued seasons: His year on the Non-Football Injury list works to Buffalo's benefit (and against Alonso's) in that instead of becoming an unrestricted free agent at the end of his rookie contract, he'll be a restricted free agent. Alonso will therefore be easier and cheaper for the Bills to retain for a fifth season than either Brown or Bradham at this point. (In that same line of thought: Bradham, a free agent after the 2015 season, might be the most appealing name to float in trade talks.)
• Coverage: As good as Brown was defending the pass as a rookie, and even considering how athletic Bradham is, Alonso is still the Bills' best coverage linebacker by a country mile. In fact, he has the potential to be one of the best coverage linebackers in the entire NFL for a long time. It is exceedingly difficult to justify trading that type of player in a division featuring Tom Brady.
• Depth: The Bills don't have to trade any of these guys. All of them are young (the oldest, Bradham, will turn 26 as the 2015 regular season begins) and cheap. Their depth at linebacker, even without Spikes, is enviable. Ryan is a creative dude. Taken as a group, these three linebackers have complementary skills; there really isn't anything that a NFL linebacker is routinely asked to do that at least one of them can't handle at a high level. Isn't depth worth preserving, even if a good player is going to be on the bench more often?

The Bills' sudden, unexpected, and enviable depth at linebacker will work to their advantage in the 2015 league year, one way or another. Either they'll have an abundance of talent to work with on game days (perhaps even too much, given scheme constraints), or they'll have the name of a talented young player to throw into the mix as they try to get better in other areas this offseason. That's a win-win - even if Alonso's name is the one being floated.