The Los Angeles Chargers took a big step toward improving their defense on Thursday afternoon by trading for Chicago Bears defensive end, Khalil Mack. Per Ian Rapoport of NFL Network, the Chargers sent second and sixth round picks to the Bears for the former Defensive Player of the Year with the intention of Mack and Joey Bosa forming one of the best pass-rushing tandems in the NFL. However, the acquisition of Mack does more than just bolster the Chargers pass rush.
Brandon Staley had just turned the Los Angeles Rams into the best defense in the NFL when the Chargers came calling. The Rams defense led the NFL in EPA/play and were first in weighted DVOA, all while giving up less than 300 yards per game. They were blessed with the perfect blend of coaching and talent, even if it didn’t lead to playoff success in 2020. It was still enough for the Chargers to hire Staley as their head coach.
The plan was simple: the Chargers front office wanted Staley to help improve a defense that allowed 26.6 points per game while helping the potent offense continue to flourish. Overall, the Chargers defense was an average unit, but likely lacking the talent to replicate the success of the Rams defense a year prior while using the same defensive scheme.
That notion proved to be accurate in 2021. The Chargers pass defense was below-average in most metrics. They finished 19th in pass DVOA and 21st in pass EPA, while allowing 221 passing yards per game. It was a slight drop off from 2020, but nothing alarming. It was the run defense that caused major concerns.
Only the Pittsburgh Steelers and Houston Texans allowed more yards on the ground in 2021, but the Chargers finished dead last in defensive success rate against the run and 31st in rush EPA. There’s no other way to say it, the Chargers were an abysmal unit against the run and a lot of their issues stemmed from the defensive line.
From a talent standpoint alone, the Chargers were undermanned in the trenches. Joey Bosa has been one of the best edge defenders in the league when healthy, but he alone isn’t enough to turn the tide. Especially when his own performances against the run were less than satisfactory in 2021. Bosa had a grade of 68.4 against the run, per PFF and had 16 run stops off the edge, tied for 25th among all edge defenders.
That was also the best grade among all of the Chargers defensive line. And for good reason. Per Football Outsiders, the Chargers were 26th in adjusted line yards, an indication that the defensive line aren’t exactly run-savvy. In fairness, the Chargers also ranked 28th in second-level yards too, which indicates that once the running back comfortably ran through the defensive line, he had a good chance to get past the second-level and rip off a big run.
Considering the Chargers allowed 4.6 rushing yards per attempt, the numbers back up that thought process. All of this is to say that trading for Khalil Mack could be the stepping stone to a better, more stout run defense for the Chargers. Mack has been one of the best pass rushers of his generation, racking up 80 sacks and 528 total pressures in his eight year career.
But it’s Mack’s overall versatility that has made him into a generational talent. Up until last season, when he played in just 7 games, Mack made a living as one of the best run-defending edges in the NFL. He’d averaged a run defense grade of 88.1 in his first seven seasons in the NFL, accumulating 293 stops in the process. Mack has the speed to chase down a running back as the weak side defender on a run play, the instincts to shoot running lanes, and to shed blocks with raw power.
The Chargers still need to significantly bolster their defensive line as Mack by himself isn’t enough to change LA’s fortunes, but paired with Bosa, who has been an above average run defender in his career, they’re likely to see results sooner rather than later.
-Thomas Valentine
Twitter: @ThomasValenfine