From his 6’5″ frame hang nearly 34-inch long arms, creating a towering pass-rusher that has off-the-charts potential. When his size blends with his athleticism and explosiveness, he becomes a rare prospect that’s arguably the most impressive in this May’s draft.

But there needs to be more to a prospect than size and athleticism. Technique and tools are necessary, such as powerful hands and disciplined pad level. That’s where questions start to arise with UCLA’s Anthony Barr, who can be one of two different players on any given Saturday.

He can be dominating or dominated.

Barr, the dominating: The one who is wide in a two-point stance at the ghost five-technique and is the first off the line of scrimmage, running past slow-footed left tackles whose only hope is hooking the pass-rusher like a basketball power forward driving to the hoop.

Barr, the dominated: The one who is wide in a two-point stance at the ghost five-technique and is the first off the line of scrimmage but fails to run past the quick-footed left tackle who mirrors his every move and gives one solid punch to knock the pass-rusher off-balance, eliminating him from the play.

His flashes of potential have reeled in NFL scouts despite the majority of his tape being questionable. They’re obsessed with the physical traits that can be measured, the same ones that Bill Walsh once called “artificial.” The numbers pop off the page, and at times, they translate.

In the three cone drill at the NFL Scouting Combine, which measures change of direction ability, he timed in at 6.82 seconds, the lowest among the top five at his position on It shows up when he’s dropping into coverage or turning the edge, as seen on one of his two sacks against Oregon this past season.

He was at right outside linebacker in the Bruins’ two-man front on third-and-11. With his left leg creased 90 degrees at the knee and his right leg staggered one-yard back, Barr was set to explode off the line and battle the Ducks’ left tackle one-on-one.

He came forward with his back flat and then raised his shoulders up when the left tackle kick-slid outside. As Barr neared the blocker, he squared his hips inside as if he was bull-rushing before kicking his right leg back out. Simultaneously he lowered his head like he was finishing a marathon, extended his arms to push the blocker’s hands away as he turned the corner.

The blocker tried to slow Barr down by running his hand across Barr’s facemask, but refrained from holding in fear of getting penalized.

As Barr turned the corner, the quarterback hopped forward in the pocket. He couldn’t avoid Barr, however. Barr stuck his right foot in the ground and leaned in, extending his 33.5″ arms for a strip-sack (00:40). This was him at his best, a dominating pass-rusher who looked like a top draft choice and eerily similar to St. Louis Rams’ Robert Quinn.

Three weeks later, he had another sack on a similar rush against Washington but was otherwise not as effective. No quarterback hurries or forced fumbles. On one particular play, he was forced to engage at the snap, and he struggled.

It was second-and-10. Barr was once again an outside linebacker on the right edge, set to face the left tackle on an island. It was the ideal situation for him, seeing how he had a speed advantage.

But when he came off the line, he stood up unlike the rush against Oregon. Then he locked out his elbows and hit the blocker’s chest plate. The punches barely moved the blocker, instead keeping separation between the two and allowing the blocker to sit back to fend off a potential speed rush — Barr’s go-to move.

Barr stutter-stepped and tried to turn the corner on the blocker, who slid his feet and punched him wide. Without his speed, Barr wasn’t a factor, looking like the San Diego Chargers’ Larry English (2:30).

For all his potential, this is where the questions with Barr come in. He’s clearly athletic and flexible enough to turn the corner, but can he do it when he’s been redirected?

At the moment, he can’t. He’s not good enough with his hands or his balance, which he’s unlikely to improve on in the pros. If he’s going to make it in the pros, he’ll have to get better with his hands and add an inside move, such as a spin that’s perfectly done by Dwight Freeney.

Two weeks after the Washington game, he was exposed at times by Southern California in this same area despite logging three sacks.

It was the fourth quarter. USC faced second-and-6 inside their own 25-yard line, where Barr lined up as a right outside linebacker in the Bruins’ 3-4 front. He was in a similar stance as before: left leg slightly flexed, right leg staggered and ready hands.

At the snap, he came hard off the line and directly upfield, going for the speed rush around the corner. The Trojans left tackle mirrored Barr’s steps to the 20-yard line, where he stuck his arms out and punched Barr. The punch slowed Barr down, causing him to lose momentum and forcing him to stop in his tracks. He tried to spin back inside but didn’t get any movement. The blocker widened his feet, forming a firm base and sat in his stance. And just like that, Barr was dominated (8:10).

Going into May, teams still have time to study Barr’s game further. That may not mean much, though, because Barr’s games are inconsistent throughout. He runs hot and cold.

When he’s hot, his speed rush is dominant, and he occasionally flashes an inside spin move. It shows that he’s conscious of the opening inside, even if not at all times.

When he’s cold, his speed rush is neutralized, and he’s barely effective. He’s not a factor in the game, leaving the viewer wondering if he’s worth a first-round selection.

What that means for predicting his NFL success is uncertain. He can be dominating or dominated, which is something the team that puts his name on their draft card will have to live with. After all, they won’t know who they are getting until a few years into his career.