Javon Hargrave had his best NFL season with 6.5 sacks in just his third year. But his contributions in run defense were just as vital to the chemistry of the defense and provide a challenge the Steelers' coaches must embrace for their 2019 defense.
We take a look at what that means, why Hargrave is so important, and the grades of the Steelers' defensive line for 2018:
The Steelers have been known as a 3-4 defense for decades now, but in recent years, that hasn't been the team's bread and butter. Their personnel packages consist of more four-man fronts and sub-package use than the 3-4 these days. In fact, they only used a 3-4 defense 302 times in 2018, just 28.93 percent of the total 1,044 defensive snaps.
The idea the 3-4 is the base defense of the Steelers is much more loose of a construct than it has ever been. But part of that is because the Steelers need to adapt to how the NFL plays. The 3-4 is great for run defense and rushing the passer if you have the right personnel, but the formation only allows for four defensive backs, and without a prime cover linebacker such as Ryan Shazier, it exposes the team's linebackers to difficult coverage matchups.
The Steelers have relied on the 3-4 since 1982 because they had the personnel to fit the scheme. But with only one prime edge rushing linebacker in T.J. Watt and no premier cover linebacker, Keith Butler and Mike Tomlin have tinkered with the defense to find any advantages possible.
That's led to more sub-package defenses, but it also puts a strain on the team's two best linemen: Cameron Heyward and Stephon Tuitt. Both are very good 3-4 defensive ends, while also being very good defensive tackles in four-man fronts. They also can play as edge rushers in those same four-man line formations.
The Steelers needed relief from having to rely on the two so much, and the surge of Hargrave's improved play opened the door for that.
Hargrave proved to be a feisty player in his first two years, recording two sacks in each season. But he exploded in 2018 with 6.5 sacks.
One of the key roles Tuitt and Heyward fill is absorbing double teams to swallow up gaps and keep linebackers clean. Doing so allows the Steelers' faster players to make plays and read without disruption. Hargrave was good at one-on-one plays in his first two seasons, but his 6-foot-2 305-pound frame put him at a disadvantage against huge offensive linemen.
That was negated by improved fundamentals in the middle of the line. Watch how he takes on this double-team against the Jaguars where he stands up the center and right guard to prevent Leonard Fournette from finding a clean gap to attack. While Hargrave doesn't record the tackle, he forces Fournette to hesitate and Watt gets the clean look to make the tackle for minimal gain:
Winning against the run, regardless of formation is huge for a player who can rotate between formations regularly. Tuitt and Heyward naturally attract double-teams because of their profiles, which gives Hargrave one-on-0ne opportunities. Watch how he does just that against the Bengals when he destroys center Trey Hopkins. He doesn't finish the play, but he opens the door for Tuitt and Watt to do just that:
Hargrave is ready for the heavier workload. He's always been a scrappy fighter within the interior of the defensive line, but needed to improve his footwork and hand placement to be consistently disruptive. Now that he's winning more battles, totaling more sacks and taking on double-teams much better, he could be a third option as a lineman that plays on the 3-4 and regularly within a sub-package defense.
What's special about that?
It means the Steelers might actually be able to rely on four-man fronts more regularly, and having that front consist of the defense's better players. Bud Dupree is an adequate speed rushing 3-4 outside linebacker, but loses value as a pure edge rusher in a four-man front.
But if the Steelers employ Heyward, Tuitt and Hargrave along with Watt in a traditional front, they would have the option to flip either Tuitt or Heyward as edge options to be opposite of Watt, while the option to rotate Hargrave, Tuitt or Heyward through the two interior lineman options.
Such a front could allow for an aggressive front to work both against the run and the pass. And that success would allow the Steelers to get more creative with seven-man coverage packages behind them. That starts with Hargrave being more in the mix. He played exactly 455 snaps in both 2017 and 2018.
The Steelers should consider increasing that number along with the variety of coverage packages in 2019.
Final Grades: Defensive Line
Here’s how these will work: We will grade each unit on the team and display how the players did through each quarter of the season, with each quarter represented by four games. Our War Room series has graded players on our stars and skulls system, so it’s time to add them all up and show their final marks.
Each game was graded on this scale:
Had a big play or a decent game 
Very impressive, multiple big plays
Elite performance
Gave up a big play without redemption 
Total performance was a disappointment
Horrible, inexcusable
If a player was average or unremarkable, they received no mark for that game. We have tallied all their performances to see who was the top of the class.
Valedictorian: Cam Heyward
First Quarter: 5 0 4 Games
Second Quarter: 50 4 Games
Third Quarter: 90 4 Games
Fourth Quarter: 100 4 Games
Final Marks: 290 A+
Best Game: Week 11 at Jaguars
Worst Game: Week 3 at Buccaneers
Heyward is still the leader of the unit and arguably the best player on the defense. He not only accounts for his responsibility on almost every play, but he wins his assignment. He so often succeeds that offensive lines prepare for an entire week to double-team him and neutralize his presence on the field. Even when all that is done, Heyward still takes advantage of every mistake.
Watch this key red zone sack on the Steelers' season finale, when Heyward stunts to the outside, freezing the guard and eventually getting the one-on-one with the left tackle. As soon as the mistake was made, Heyward was in the backfield and the play was over:
I could do an entire series on the many things Heyward does right, and maybe I will soon, but the point is he's still a monster on the defensive line.
Stephon Tuitt
First Quarter: 3 2 4 Games
Second Quarter: 50 4 Games
Third Quarter: 20 2 Games
Fourth Quarter: 80 4 Games
Final Marks: 182 B
Best Game: Week 8 vs. Browns
Worst Game: Week 2 vs. Chiefs
Tuitt had a slow start to the year and still didn't amass the sack numbers to compare him to Heyward's best seasons with just 5.5 in 2018, but he was a disruptive force. He drew double teams regularly and, like Heyward, would explode as soon as he realized an offensive line overlooked him. Watch how he takes on the right guard and rushes through A-Gap to get Andy Dalton. While the center is too busy worrying about Vince Williams, Tuitt abuses his man and records the sack:
Tuitt's biggest contributions came on how teams would prepare to stop him similarly to how they wanted to stop Heyward. On pass and run plays, Tuitt would attract two blockers. While his numbers didn't skyrocket, that opened up opportunities for other players to win easier matchups. Watch how both Tuitt and Heyward start the play by attracting two linemen block each of them, opening up Williams with a one-on-one rush chance against Christian McCaffrey:
Williams wins that kind of matchup regularly, but teams can assign players to help against that if they aren't concerned with other threats. Tuitt is one of those threats, but he has to make the leap to be a more consistent producer in the pass rush soon. He will be 26 next year and Heyward will be 30, meaning that he needs to start taking the mantle from Heyward soon. Tuitt's best sack year was 2015 with 6.5, which Heyward has surpassed four times in his eight year career, including the last two seasons.
Javon Hargrave
First Quarter: 2 0 4 Games
Second Quarter: 20 4 Games
Third Quarter: 70 4 Games
Fourth Quarter: 20 4 Games
Final Marks: 13 0 B
Best Game: Week 11 at Jaguars
Worst Game: Week 16 at Saints
Hargrave had a slow start to the season, but he hit a surge around the halfway point that made him a key player to help the Steelers' defense. He's figuring out how to contribute more consistently against the run, and if he does, he could become a fixture for this defense for the next several years.
Tyson Alualu
First Quarter: 0 0 3 Games
Second Quarter: 00 4 Games
Third Quarter: 22 4 Games
Fourth Quarter: 00 4 Games
Final Marks: 2 2 D+
Best Game: Week 11 at Jaguars
Worst Game: Week 12 at Broncos
Tyson Alualu is the serviceable backup on the line, but nothing more. That's what the Steelers bargained for when they signed him to a two-year contract in 2017 after being the 10th overall pick in the 2010 NFL Draft. He replaced Cam Thomas as the primary interior defensive linemen that would be called up along with L.T. Walton, and was an upgrade.
But the Steelers have to recognize that with the amount of plays the defense has to endure, their linemen will get tired and fresh legs are vital to finishing games. There were too many times Alualu was called into a game and he didn't make the difference needed to be disruptive on the line.
In order to ensure the starters have fresh legs, the team needs more than just a serviceable backup to spell them. I expect the Steelers to look elsewhere at this position during free agency, or maybe even the draft. They can afford to have a couple serviceable backups, but they need at least one in the rotation that can be the occasional wrecking ball.
L.T. Walton
First Quarter: 0 0 1 Game
Second Quarter: 00 0 Games
Third Quarter: 01 3 Games
Fourth Quarter: 00 0 Games
Final Marks: 0 1 D
Best Game: Week 10 vs. Panthers
Worst Game: Week 12 at Broncos
Walton didn't get much of a chance to show his stuff all season, and when he did he didn't make much of an impact. He's the serviceable kind of player you expect down on the depth chart that can make a play here and there, but also that won't be the game-changer or cost anything to keep around.
Daniel McCullers
First Quarter: 0 0 4 Games
Second Quarter: 10 4 Games
Third Quarter: 03 3 Games
Fourth Quarter: 00 4 Games
Final Marks: 1 3 F
Best Game: Week 3 at Buccaneers
Worst Game: Week 11 at Jaguars
I was surprised Daniel McCullers was even brought back for 2018. He rarely has shown inspired play, and in the preseason looked the same as he had for years. He stepped up early against the Buccaneers with a pass rush that forced Ryan Fitzpatrick to throw a bad pass which Dupree intercepted and returned for a touchdown, but other than that his list of good plays was short.
I don't expect him to be back with the team next year, unless they go the entire offseason without finding a defensive tackle they like. In that case, McCullers will probably be unsigned again around training camp time, and might get another shot. But the team should be done with this project now.
Defensive Line Final Grade: B+
First Quarter Average: B
Second Quarter Average: B+
Third Quarter Average: B
Fourth Quarter Average: A-
Heyward, Tuitt and Hargrave were the key to the defense in plenty of games, causing pressure and totaling 20 sacks between them. Their efforts also kept linebackers clean to read running plays and get better looks at the quarterback on blitzes. For these three starters, the Steelers are in a very good position. But they need to take a look at the depth behind them to have solid spell options for 2019.
Adding a fourth interior defensive lineman who could be an aggressive pass rusher and a physical run defender would allow the Steelers to play around with the positioning of their defensive front and create more looks for offenses to study.
Every additional layer of diversity in the packages a defense can provide forces offenses to have to study, creates more challenges for them to overcome and therefore more opportunities for mistakes in communication. If the defensive line becomes malleable to various fronts in 2019, it could make life a lot easier on the coverage men behind them, especially on money downs and critical situations.
