Sione Vaki scouting report: Exploring the Utah safety's strengths and weaknesses

One of the top-1000 national recruits back in 2019, after serving his two-year church mission, Sione Vaki already started five of 14 games on defense along with heavy special teams usage in his first active football season, recording 41 total tackles, with 3.5 for loss, three pass break-ups and a forced fumble.

In 2023, Sione Vaki started all 12 contests he was available for (51 stops, 8.5 TFLs, two sacks, an interception and two PBUs), along with being a hyper-efficient part-time running back, who turned just 53 touches into 520 yards and five touchdowns. That earned him first-team All-Pac-12 accolades at both safety and the all-purpose spot.

Profile: 5-foot-11, 210 pounds; RS SR.

Breaking down Sione Vaki's scouting report

Run defense & blitzing:

Was regularly put down low and proved himself to be quality edge-setter in the run game
Outstanding lateral mobility to track wide zone concepts from the backside whilst keeping his shoulders level to the line of scrimmage
Generally does well to track the ball out to the sideline, coming to balance and shuffling along as the ball-carrier hesitates momentarily to not get juked
Has the force in his hands to punch off backs or tight-ends trying to lead up to him on sweep plays and to help wrap up the guy with the ball trying to follow
Shows the quick burst to navigate around bodies and wrap up the recipient of wide receiver screens
Does a nice job of squaring up in the alley as the ball-carrier has is being corralled and applying great stopping power with his chest to drive that guy backwards
Understands very well how to use the sideline as a 12th defender and leveraging guys on the run, not allowing them to cross him up typically

Zone coverage:

Easy in his pedal to gain depth in deep zone responsibilities
Moves around low and can change directions very well as a hook/overhang defender
Vaki’s ability to cover a lot of ground was used when Utah started him down low and had him fly out to a deep half or the post, to change up the picture on quarterbacks
Alert for crossing routes when he’s pulled up based on formation and playing zone down low, flying underneath them and forcing quarterbacks to find a different solution
Sorts through traffic well on divide concepts and other stuff where receivers release out of stacks/bunches, to locate who he’ll attach to
Does well to read the eyes of the quarterback and drift underneath routes in his vicinity, making that guy turn down throws
When Sione Vaki sees that ball come out, Vaki zooms up in a flash to shut down any YAC opportunities – delivering a good pop when he gets a chance – and he quickly barrels down on scrambling quarterbacks

Man coverage:

Packs a strong punch to impede the progress of tight-ends pushing at him in off-man
When lined up in (soft) press, Vaki has the quick laterally to match the release of his opponents and impede their progress, having to go through him
Very tight in his change of direction and doesn’t get lost against whip/pivot routes
Understands when to take his hands off the guy he’s covering in order to avoid getting flagged – zero penalties across basically 1000 defensive snaps
His speed was and affinity for contact was used blitzing off the edge a few times
Thanks to his ankle flexibility, he can turn a tight corner and dip underneath tight-ends staying in protection – on 17 pass-rush snaps last season, he logged nine pressures
While Sione Vaki does want to play defense primarily, having someone in the pocket who averaged nearly ten yards per touch as a running back and who played slot receiver in high school is definitely a plus (also averaged an insane 47.6% missed tackles forced per carry)

Weaknesses:

Needs to be a little more disciplined with his contain responsibility when he’s lined up over tight-ends and ends up having to lock horns with them
Could do a better job of wrapping and driving through tackles on an angle, which those 29-inch arms definitely aren’t helpful at – missed 14.3% of attempted tackles last season
On multiple occasions had to adjust his initial angle ranging out against vertical throws as a single-high safety
There’s room to improve how he squeezes down space and to not gain excess width or depth as a deep half defender in particular
According to PFF’s numbers, on 127 snaps in man-coverage last season, Vaki allowed eight of 11 targets his way to be completed for 96 yards and a touchdown (129.4 passer rating)

Sione Vaki's 2024 NFL Draft prospect

Sione Vaki is one of the more interesting players in this draft. He came to Utah back in 2019 yet didn’t even see the field until two years ago and logged just under 1000 career snaps on defense, due to the church-mission he served.

Considering the limited development opportunities, there’s a lot to like him about him on tape as kind of a do-it-all defensive back. Yet, I’m not so sure that if he committed to being a running back, he wouldn’t potentially be an early day-three pick based on that alone, considering how effective he was in limited capacity.

Whether it’s positioning himself accordingly based on the pattern in zone coverage, staying true to his assignments against the run or finishing his tackles more reliably, there are still clearly things for him to iron out.

Being fairly short and running a 4.62 at the combine won’t give him a big margin for error to prove himself to the coaches early on, but watching him go through the positional drills, there aren’t many guys who move and redirect as effortlessly as this guy.

Combining that with his fearless attitude, I think he could be a core special teamer early on to earn opportunities to contribute on either – if not both – sides of the ball.

Grade: Fourth round