University of Arizona vs BYU

Arizona edge rushers Jalen Harris, left, and JB Brown combined for 6.5 sacks last season 

Our Arizona Wildcats spring football preview continues with a shift to the other side of the ball.

We’re examining two positions per day all week leading up to the start of spring practice on Monday. Links to all the other previews can be found at the bottom of this post.

EDGE RUSHERS

Key returnees: Justin Belknap (6-3, 259, RS SR), JB Brown (6-3, 263, JR), Jalen Cochran (6-3, 263, RS JR), Jalen Harris (6-4, 230, RS SO), My-King Johnson (6-4, 227, RS SO), Kylan Wilborn (6-2, 248, JR)

Key newcomers: Eddie Siaumau (6-3, 215, FR), Kwabena Watson (6-2, 225, FR)

(*-midyear enrollee)

The big question: If someone in this group doesn’t surpass last year’s leading sack total of 3.5, is the UA defense in trouble?

Sacks aren’t the end-all, be-all when it comes to measuring the effectiveness of a pass rush. Hurries and knockdowns can have just as big an influence.

Pro Football Focus’ “Pass Rushing Productivity” rating measures pressure created on a per-snap basis, with weighting toward sacks.

Per PFF, Harris ranked sixth among Pac-12 edge rushers in 2018 with a PRP of 8.0. (The league leader, Porter Gustin of USC, had a PRP of 10.0.) PFF credited Harris with five sacks (two more than his official count), six QB hits and 20 hurries in 231 pass-rush snaps. Not bad.

But if you asked Harris or any other UA defender about their 2018 sack totals, they’d say they didn’t have nearly enough.

While imperfect as a statistic, sacks still matter. They literally can end drives or change games.

As a team, Arizona ranked ninth in the Pac-12 in sacks (23) and sacks per game (1.92). Those numbers were down from 31 (in 13 games) and 2.38 the previous season.

(Sack fun fact: Washington – which allowed the fewest yards and points per game in the Pac-12 – had one fewer sack than Arizona in one more game last season.)

If you’ve spent any time watching the UA defense under Marcel Yates, you know the Wildcats would benefit from a more consistent pass rush – especially in those maddening third-and-long situations.

Four Wildcats had three or more sacks last season. One of them, linebacker Colin Schooler, who tied with Brown for the team lead at 3.5, is a part-time pass rusher who has many other responsibilities. Another, PJ Johnson, was primarily an interior lineman. He’s now prepping for the NFL draft.

The two others who hit that threshold were Harris and Brown. They’re two of the top three candidates to boost Arizona’s sack total. All three are entering their third seasons. They can still get better.

Harris might be on the cusp of a breakout. He has everything you want in a pass rusher – quickness, speed, length and desire. He’s just constantly waging the battle of the bulk. If Harris can come anywhere close to his stated goal of 260 pounds (245 would suffice, honestly) without losing any of that burst, he’d be a force.

While Harris eventually became the starter at “Stud,” Brown emerged on the opposite side after Belknap suffered a season-ending foot injury in September. Although he isn’t blessed with Harris’ seemingly endless arms, Brown has developed into an effective rusher. Not only did his 3.5 sacks tie for the team lead, his 7.5 total tackles for losses ranked third.

Considering that he moved from middle linebacker during his freshman season, Brown still has upside. Arizona has the makings of a nice DE rotation with Brown, Belknap and Cochran (if he can stay healthy, which has been a problem).

Surprisingly, Brown ranked lower in PFF’s PRP metric (31st among Pac-12 edge rushers) than Wilborn (26th). The latter’s drop in production remains one of the biggest lingering mysteries of the 2018 season.

Wilborn looked like a budding star as a freshman, when he recorded 7.5 sacks and led the Pac-12 with four forced fumbles. He appeared to be continuing his ascent during training camp. Then, when the games started, Wilborn all but vanished.

Wilborn finished with two sacks and one forced fumble. He had only 14 total tackles in 11 games (Brown had 30, Harris 27).

Did opponents figure out Wilborn’s game? Did he add “bad weight,” as message-boarders have theorized, diminishing his quickness and agility? Did he have injuries that never became public?

Whatever the case, Wilborn wasn’t the same player in 2018. He still has time to rediscover his freshman form. A re-emergence of the ’17 Wilborn – combined with the continuing development of Brown and Harris – could make all the difference for the UA defense.

UA SPRING FOOTBALL PREVIEW

Contact sports reporter Michael Lev at 573-4148 or mlev@tucson.com. On Twitter @michaeljlev