By Logan Lamorandier | Twitter @llamorandier

When the Lions and general manager Bob Quinn selected linebacker Jahlani Tavai in the second round of this year's NFL Draft, there was some question as to what exactly Tavai's role would be in the defense.

Due to a preseason ankle injury for former first-round selection Jarrad Davis, Tavai's playing time was augmented by default.

The rookie acquitted himself nicely in the first two weeks of the season. Since then, though, the now-healthy Davis has usurped a majority of the MIKE linebacker reps.

Tavai played a total of 107 defensive snaps in the first two weeks compared to 40 in the last two games.

Meanwhile, Davis has logged 131 snaps, and has rarely left the field in his two games since his Week 3 return.

According to Pro Football Focus, Davis has been the worst graded off-ball linebacker in the league (minimum of 75 defensive snaps).

Can't say for sure, but Davis is still likely battling the effects of his high ankle sprain. That is an injury notorious for lingering.

It's not as if Tavai's PFF grade is off the charts, as it's still in the lower average range.

To give Davis some credit, despite playing the same position, Tavai and him are utilized quite differently.

The PFF grading system is by no means perfect, but should the underwhelming Davis relinquish some of his snaps to the promising Tavai?

Let's take a closer look.

RUN DEFENSE

Tavai is a special kind of linebacker; hence, the reason for the Lions taking him higher than most national NFL Draft pundits expected.

His size and versatility are rare -- something that Lions head man Matt Patricia covets. He is almost 250 pounds, and is difficult to move.

Davis, on the other hand, was drafted to be a traditional 4-3 middle linebacker, and possesses elite athleticism.

To better suit what is being asked of him in Patricia's hybrid defense, Davis added some weight in the offseason. Even after bulking up, his style of play is still more "run and chase."

Unlike Tavai, Davis does his best work when tracking ball carriers, but has a tendency to try to go around lineman instead of holding his ground at the point of attack. When he does engage blockers head-on, it's a battle he does not often win.

Maybe the most impressive part of Tavai's game so far has been his aptitude to hold his ground, then stack and shed opponents who are bigger than him. He is difficult to move out of running lanes.

His game speed is faster than his timed speed, but he still isn't a sideline-to-sideline linebacker like Davis.

What's nice about the Lions’ defense is that it emphasizes outside contain against the run and doesn’t always need speedy linebackers to beat running backs to the edge.

In terms of missed tackles, Tavai has struggled in that department.

One of the biggest complaints of Davis has always been his tackling inconsistency and over-running of ball carriers. In this season's small sample size, Davis has a slight edge in tackling efficiency, though.

Overall, the two linebackers have different styles of play, but both have their pros and cons.

PASSING DEFENSE

This is where the comparison turns to apples and oranges.

When in passing situations, the Lions place plenty more coverage responsibility on Davis' plate. Almost 83 percent of opponents’ pass plays this year have resulted in Davis dropping back in coverage.

The same cannot be said about Tavai.

Patricia limits what Tavai does in space, and instead uses Tavai as a movable chess piece rushing the passer. Tavai is rushing the quarterback on 39 percent of the opponents’ passing plays.

In the first two weeks, when Tavai was seeing extended playing time, he had the second-most pass rushes for all off-ball linebackers in the league. In that span, he had five total quarterback pressures, including one sack. Fair to say, he was producing.

That's not to say that Davis can’t get after the quarterback, either.

Last year, Davis had the second-highest pass rush productivity in the NFL for off-ball linebackers.

In fact, in 2018, Davis was just one of two NFL defenders to amass 100-plus tackles and six-plus sacks -- the only player in Lions history to accomplish that feat as well.

A big reason that Davis is so low on the PFF grading scale is because of his coverage grade.

Despite often being in decent position, Davis has demonstrated he doesn't have the ball skills and instincts to make a play on the ball.

Unfortunately, Davis is the most athletic linebacker on the team, and none of the Lions’ starters are great in coverage.

It just so happens that Davis is probably the best bet in regard to Detroit’s top-three linebackers, even with his struggles. Someone has to do it, which is why Davis gets the call, at the expense of his overall PFF grade.

On a separate note, the Lions bring just three rushers the most often of any NFL team. That leaves an extra defender in coverage or a QB “spy” -- another role Davis often finds himself in.

He is a major reason the Lions gave up the fewest rushing yards allowed to quarterbacks a season ago.

Logan’s Final Thoughts

It is very likely that Davis can do things Tavai just can't.

Davis is put in difficult situations against some of the best athletes in the NFL.

Outside of backup LB Jalen Reeves-Maybin, Davis is the go-to linebacker when the Lions need to cover running backs out of the backfield.

To this point in his career, Tavai has been a two-down LB that is used on stunts in an effort to bring pressure on obvious passing downs.

Maybe it will be a weekly matchup decision, but I hope Patricia can find the burgeoning Tavai a larger role in the defense moving forward.

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