NFL Draft 2015: PFF analyzes top linebackers, potential busts and late-round sleepers

This isn't a strong class for linebackers in terms of first-round talent, but there's plenty of quality backers to be found on Days 2 and 3 of the 2015 NFL Draft.

Both points are evident in Pro Football Focus' analysis of the top LB prospects. Of the possible first-round backers in this year's draft, Mississippi State's Benardrick McKinney, TCU's Paul Dawson, Washington's Shaq Thompson and UCLA's Eric Kendricks are all possible Day 1 picks.

However, McKinney and Thompson are both featured in PFF's Buyer Beware piece. Thompson specifically has be a Bengals favorite in mock drafts this season [here, here, here, and here], largely because the Bengals have a lot of questions surrounding all three LB spots.

WLB Vontaze Burfict could open the year on PUP. MLB Rey Maualuga is more of run defender and a huge liability in coverage. SLB Emmanuel Lamur had a poor 2014 season and is on the final year of his deal. All of this could lead to Thompson being high on Cincinnati's big board, but as PFF notes, he's a risky prospect.

Thompson isn’t close to NFL caliber in three of the main aspects you look for in a linebacker playing between the tackles: run/point of attack recognition, downhill angles of attack, and ability take on/shed blocks. The only run aspect Thompson has down is his ability to locate a ball carrier and tackle in space. That’s certainly a desired trait in today’s NFL, but with all the knocks against him it’s hard to project him as anything other than below average against the run.

Signature Stat: Thompson’s 7.3 Run Stop Percentage was 41st among 58 draft-eligible inside linebackers.

If the Bengals want to add a LB or two, they may be better off waiting until Day 3 or until undrafted free agency. That's what they tend to do anyhow, and PFF also previewed some of the top sleeper LBs in this year's class.

The first name they mentioned is Utah State's Zach Vigil. The 6-2, 240-pound  LB notched 20.5 tackles for loss and nine sacks this past season. The Bengals need to get more pass rushing skills from their LBs, and adding Vigil could help that effort.

The middle linebacker graded well above average rushing the passer, in coverage, and against the run. Vigil’s 76 total stops were the second most in the draft class and his 36 total pressures were the second most as well. He was also a very reliable tackler missing just 12 all year compared to 131 combined solos and assists.

Signature Stat: Vigil had a 12.9 Run Stop Percentage last season, but that number jumped to 14.3% against the Power 5 schools he faced.

Another name to watch in the latter rounds is Boston College's Josh Keyes. His college numbers don't jump off the screen: 96 tackles, 16,5 tackles for loss and 7.5 sacks over the past seasons. However, PFF found that Keyes was very productive from an advanced analytic standpoint:

Keyes led all off-ball linebackers in hits (10) and hurries (28). Pass rushing ability as an off-ball linebacker is a very strong indicator of that player’s ability against the run as they require similar skills (shedding blocks, aggressiveness, power, etc.).

While his pass rushing ability is a huge plus, what really stands out to me about Keyes game is just how fluid of an athlete he is. He looks like an overgrown safety the way he can turn and change directions. The only problem is that at 6-foot-2 and 230 pounds he might be limited to a 4-3 weakside linebacker in the NFL.

Keyes was forced to make many of his plays in space, which makes his 11.2 Tackling Efficiency (eighth-best among outside linebacker prospects) all the more impressive.

Signature Stat: Keyes wasn’t just racking up unblocked pressures, 27 of his 42 total pressures came after beating a block.