An athletic linebacker would be missing piece for improving Packers defense

When Blake Martinez could flow to the football thanks to Kenny Clark and Mike Daniels soaking up blockers, he “led” some excellent run defending groups, wracking up tackles. When Mike Pettine started experimenting with smaller fronts, fewer defensive linemen, and more cover plays, all of a sudden Martinez’s impact play fell off a cliff, exposing his lack of elite instincts, physicality, or athleticism.

The 49ers didn’t kill the Green Bay Packers by running down their throats up the middle, but rather on the edges, knowing Martinez and B.J. Goodson lacked the juice to get to the sideline even with a good edge set by the outside linebackers.

More importantly, Martinez’s inability to cover effectively, whether in space or in man coverage, forced Pettine played more zone against bigger offensive lineups, making the defense too predictable. That would be one thing if Martinez were a playmaker extraordinaire like the linebackers opposite him in San Francisco. The sad reality for the Packers is the 49ers boast three linebackers who played better last season than any linebacker in Green Bay, including the guy who led the league in tackles most of the season.

Brian Gutekunst and Pettine face a vital question for their defense: are they comfortable not prioritizing linebackers, preferring instead to boost a defensive front that can make life easier on those linebackers? To put a finer point on it, did the Packers play small because they had to — because Martinez wasn’t athletic enough to help in coverage and the defensive line wasn’t great — or because that’s how Pettine wants to play?

The evidence we have suggests Pettine prefers to play this downsized style. Even when he had a deeper group of defensive front players and a weaker secondary, he preferred to play small. At this point, we can safely say his view of defense, to stop the pass first, reflects a desire to rush with four, cover with seven, and play the football version of small ball.

Much like in basketball, small ball lineups work when players possess versatility. If there are only five true “front” players on the field, then those five guys better all be able to handle their responsibilities with aplomb. Though the Packers lack depth up front, their talent at the top rivals any team in football ... except at linebacker.

One argument would be get better upfront, find that piece to go next to Kenny Clark and Dean Lowry who can consistently impact the game. From a run defense standpoint, there’s some wisdom in that. Even with an upgrade at linebacker, wouldn’t it be nice to ease his responsibilities and make him even better? In that way, sure, it makes sense for the Packers to seek an upgrade there.

That said, the linebacker spot deserves the more pressing attention. Unless they somehow hit on some high-impact pass-rushing interior defender, the linebacker spot impacts the game in more ways.

Eric Kendricks played at an All-Pro level last year to the point I considered him for DPOY in the PFWA voting. Pro Football Focus graded him as the third-best run-defending linebacker in the NFL among players with 20% of snaps. Kendricks thrived despite the the interior defensive line for the Vikings playing well below average.

Linval Joseph’s run defense grade landed him at 50th among defensive linemen, while Shamar Stephen finished 94th. For comparison sake, the Packers had three defensive linemen grade better than Stephen, including Kenny Clark at 58, just a tick behind Joseph despite a slow start to the season.

Yet the Vikings ended the season in the top-10 of run defense DVOA, and the Packers managed the 23rd-ranked unit. By all rights, the Packers have the better group of players with Za’Darius Smith, Preston Smith, and Kenny Clark presenting a better trio than any the Vikings have to offer, plus the Vikings have the weakest link. The biggest difference between them is Kendricks. He makes the group tick.

Linebackers covering up for holes in front of them isn’t unique to Kendricks. Bobby Wagner, Damario Davis, Luke Kuechly, Darius Leonard and most of the other top linebackers in the league thrive without Sam Adams and Tony Siragusa in front of them.

Even before the 49ers put together the best defensive line in football, Fred Warner starred behind them. Kwon Alexander, now a 49er, wreaked havoc with Lavonte David despite a thoroughly uninspiring group of defensive linemen outside of Gerald McCoy. Defensive lines make life easier on linebackers, but good linebackers impact the game regardless of their supporting cast.

What’s more, their impact in the passing game exists independent of the play in front of them. Sports Info Solutions’ advanced numbers back this up. According to SIS’ Points Saved numbers, Nick Bosa led all front players with 61 points saved, and Aaron Donald finished second with 51.

Seven linebackers finished ahead of Donald, including guys like the aforementioned David, Leonard, Kendricks, and Davis who didn’t have much interior help “staying free” as it were. That’s because they affect the game in coverage and getting sideline to sideline as well. The game isn’t the downhill, smashmouth affair from the 1990’s. Range and playmaking reign.

There’s a silver living in the way Pettine plays that could make it easier to find that impact player. Pettine’s desire to play small takes some coverage duty off the plate of whoever steps into that role. In other words, it doesn’t have to be a guy who can stick with Travis Kelce in one-on-one situations. That’s why they have players like Ibraheim Campbell and Raven Greene. The Chiefs, for example, often used Tryann Mathieu on George Kittle in the Super Bowl, and the 49ers liked their matchup with Richard Sherman on Kelce. This is how modern football looks.

In the draft, Oklahoma’s Kenneth Murray, for example, rarely played in man coverage or even much in deep zone. In fact, most inside linebackers in the college game play this way because so many college teams have taken the same downsized approach to defense. Murray, though, flies downhill to the ball, gets sideline-to-sideline with ease, spies the quarterback well, and kills opponents as a blitzer. Green Bay doesn’t need Brian Urlacher in the middle of the field. They need a fast, nasty inside ‘backer who impacts the game upfront and can still provide some value in coverage.

Stick him next to Raven Greene, who will get more assignments defending backs and tight ends, and the Packers suddenly possess a significantly more dynamic tandem.

It wasn’t only that Blake Martinez couldn’t cover, it was that his lack of playmaking and athleticism subverted the strengths of the players around him by limiting what they could do with his own limitations. Whether they believe Oren Burks or Curtis Bolton can step into that role will dictate how aggressively they pursue free agents and high draft picks at the position. Burks and Bolton each flashed coverage skills in preseason and Pettine used Burks extensively last August next to Martinez in his nickel packages, then didn’t use him much in the regular season. Each will likely get a shot to earn the starting job in 2020.

The Packers could improve the defensive line, though Gutekunst offered praise and support for the young players already on the team. That won’t, however, bolster the defense nearly as much as finding the middle-of-the-field attacker at linebacker, one who can impact the game with or without the help of his friends.