Aaron Donald's Speed Could Make Him the NFL's Next Great Defensive Tackle

St. Louis Rams rookie defensive tackle Aaron Donald is small, but you may have already forgotten that. He doesn't give you much of a chance to notice while leaving much larger men swatting at little more than air.

Donald is small, but he plays fast. So fast that speed alone will push him to the top of his position early in his NFL career.

Pardon me if that smells a little of hyperbole right now. Donald will play only his eighth NFL game this Sunday and start just his fourth. At this point he’s still trying to develop like any rookie who hasn't played even half a season yet.

But go ahead and watch game tape of Donald's play so far. Quickly his lack of experience won't matter as you watch his uniquely punishing speed.

While doing that, make a note that there’s no shame in wearing an adult bib of some kind to catch the waterfall of drool.

He’s not small when compared to most mere mortals. There’s nothing tiny about being 6’1” and weighing 285 pounds, measurements that would definitely make you stop, try really hard not to stare, and think “whoa, that guy must be a football player” upon seeing him in public.

That assumption about Donald’s profession would be correct, yet at his position he’s definitely small. By comparison, Marcell Dareus of the Buffalo Bills currently leads all defensive tackles with seven sacks this season. He’s accomplished that through great feats of strength, as Dareus breaks scales at 331 pounds.

That’s 46 more pounds of human being than Donald. We can continue to go down the list with the league’s top defensive tackles, noting that other top tackles like Ndamukong Suh from the Detroit Lions (305 pounds) and Gerald McCoy from the Tampa Bay Buccaneers (300 pounds) out-girth Donald by at least 15 pounds.

Even the relatively smaller Geno Atkins from the Cincinnati Bengals—who was the default Donald comparison throughout the pre-draft process last spring—is 18 pounds heavier.

And none of that has mattered.

Donald didn’t start his first game until Week 6 against the San Francisco 49ers. Over the Rams’ first four games he played an average of only 27.3 snaps. He was used so inconsistently that he played only 40 percent of the Rams’ defensive snaps through the first five games of the season, bottoming out at 34.2 percent in Week 5.

And none of that has mattered.

Donald has made his presence known in a thunderous way with whatever playing time he’s received. He’s recorded 15 total defensive stops, according to Pro Football Focus (subscription required), tied for seventh among all defensive tackles despite playing only 264 snaps (for perspective, Dareus leads all DTs with 19 stops and he’s played 434 snaps).

Donald has recorded 12 of those stops in run defense. That gives him a run-stop percentage of 12.6, the second-highest total in the league (per PFF) which gets even more impressive when we once again consider his initial lack of playing time.

The 23-year-old is either ahead or only marginally behind the top run-stuffers in the league even while being in on far fewer run plays.

Player	Run snaps	Stops	Stop Percentage
Damon Harrison	125	17	13.6
Aaron Donald	95	12	12.6
Earl Mitchell	120	14	11.7
Johnathan Hankins	128	14	10.9
Brandon Williams	141	14	9.9

Harrison is well ahead in defensive stops because his immense size (350 pounds) also makes him a science experiment. But all the others are only a tick above Donald in stops even while defending at least 25 more runs.

The Rams’ pass rush has sputtered this season, a well-documented spiral that’s started to turn around. Of their league-worst six sacks, Donald has two of them while recording nine quarterback hurries. Those hurries tie him with Dareus, who’s been asked to defend 107 more pass plays.

You’re picking up on a theme here, one that San Francisco 49ers wide receiver Stevie Johnson also knows quite well. Donald has done a lot with largely little, and now as his role expands we can expect to see more interior offensive linemen baffled by his acceleration and completely unfair quickness.

At the NFL Scouting Combine last February, he was a secondary act. That was true for every defensive lineman with the spotlight squarely on Jadeveon Clowney, who was selected by the Houston Texans with the first overall pick. But Donald emerged as true superstar of the combine.

"

Aaron Donald's film backs up his claim that he's a 1st rounder. His practice & play at Sr. Bowl 2nds it, & his combine numbers screams elite

— Omar Kelly (@OmarKelly) February 24, 2014"

He may be small for his position, but a 285-pound man still shouldn’t be able to cover 40 yards in 4.68 seconds as Donald did.

When weight and height differences are factored in, it’s clear that Donald’s athleticism was unmatched in his draft class. Chase Stuart from Football Perspective did the math to compensate for the different body types running and jumping in Indianapolis. He concluded Donald produced top seven overall performances in the three major events that measure strength and explosiveness (40-yard dash, bench press and three-cone drill).

So, long before this season we knew about Donald’s freak status from both his combine dominance and his college game tape. During his senior year Donald led the country with 28.5 tackles for a loss, a product of his quick burst off the line.

What exactly does his explosiveness look like at the professional level? Mostly, it resembles cannon fire.

During the combine, Donald recorded a 10-yard split of 1.64 seconds. Translation: he has downright lethal short-area quickness and can blast into the backfield before an opposing offensive lineman even gets out of his crouch.

It didn’t take long for Donald’s fireworks to appear on an NFL field. Immediately he was greeting running backs nearly before they took a handoff.

One such warm greeting came on the final play of the third quarter in a Week 1 loss to the Minnesota Vikings. On first down at their own 30-yard line, the Vikings were showing run, with running back Adrian Peterson in the I formation behind fullback Jerome Felton.

After the Rams defensive line shifted, Donald was positioned between the tackle and guard. His assignment? Fire through the gap and disrupt the play.

Credit: NFL Game Rewind

Doing that effectively requires more than raw speed. Donald needed perfect timing to rise from his three-point stance exactly when the ball was snapped, accelerating before left tackle Matt Kalil had a chance to react.

While doing that he needed to keep a low pad level and maintain leverage. Which is much easier for Donald, when his head is already through the gap at the point of contact.

It took 0.23 seconds for Donald to establish that leverage as he breaks into the backfield. Khalil wasn’t given nearly enough time to establish solid footing and a base to drive Donald to the right. When contact is initiated his weight is almost entirely on one foot.

Credit: NFL Game Rewind

Quarterback Matt Cassel was only just turning around and hadn’t even extended the ball to Peterson yet, and Donald was already breaking through. Speed leads to an element of surprise.

With all the leverage because of his initial burst Donald was now able to control and direct Khalil. So with two more powerful strides he continued his penetration deep into the backfield. Look where he is now, and note the location of ball.

It’s still not in Peterson’s hands.

Credit: NFL Game Rewind

The play resulted in a three-yard loss, and it wasn’t even close to being Donald’s most impressive embarrassment of an offensive lineman in his first game.

That came later in the fourth quarter when Donald took right tackle Phil Loadholt for a Sunday shirt ride.

Credit: NFL Game Rewind

On another off-tackle run to the right Loadholt was trying to execute a down block, keeping Donald contained and pushed to the left. But he barely flinched before he could see the name on the back of Donald’s jersey.

Loadholt's reaction as quarterback, ball, running back and defensive tackle met at the same time was to lunge and desperately hold on. It didn’t work, and this time Peterson went down for a six-yard loss.

Another off-tackle run ended in embarrassing fashion for Tampa Bay Buccaneers guard Logan Mankins in Week 2. Yes, that’s six-time Pro Bowler Logan Mankins.

Deep in Rams territory during the third quarter Mankins shifted immediately after the snap and moved to his left. He was aiming to prevent Donald from having access to the (hopefully open) running lane where the fullback would break through and running back Bobby Rainey would follow.

Credit: NFL Game Rewind

But he wasn't prepared for Donald’s quick movement. Sensing Mankins’ shift to one side, Donald planted his right foot, swatted with his left arm, and gained access to the gap with a perfectly executed swim move

Credit: NFL Game Rewind

The play ended with another three-yard loss. Once more a would-be blocker who’s 20 pounds heavier than Donald was left tumbling. And once more Donald met ball, quarterback, and ball carrier nearly at the same time.

In a season that could become awful fast for the Rams with a heaping pile of hurt elsewhere on the roster, Donald provides precious hope. Alongside defensive end Robert Quinn he forms one half of a pass-rushing tandem that’s overflowing with athleticism, and Donald is highly effective against the run too.

The best part? They’re both under the age of 25.