Should Aaron Donald or Khalil Mack be NFL's highest-paid defensive player?

Aaron Donald and Khalil Mack are arguably the two most destructive pass-rushers in the league, and both Defensive Player of the Year winners are on the verge of becoming exceedingly rich men this offseason.

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But only one can take the title of the NFL's highest-paid defensive player from Denver Broncos superstar Von Miller. Let's break down Donald's and Mack's production to see who's most deserving of the honor.

Firstly, it must be noted that Mack and Donald play different positions - 4-3 defensive end and 3-4 defensive tackle, respectively.

However, Donald plays in Wade Phillips' aggressive, fluid Los Angeles Rams defense, which blurs the line between the two schematic philosophies and allows him to rush the passer consistently. That means his stats can be compared to those of the Oakland Raiders star without too much issue.

In terms of the raw numbers since 2016, not much separates the two defensive monsters. Mack has a significant lead in tackles, but sacks and forced fumbles are essentially a wash considering that Donald played two fewer games in 2017 (one due to a holdout, one due to being rested in Week 17).

Furthermore, Donald's 11 quarterback takedowns were the second-most for a non-edge defender (classed here as a 4-3 defensive end or a 3-4 outside linebacker) - behind only Cameron Heyward, according to NFL.com. And of the top 22 sack leaders in 2017 (four players tied with 9.5 sacks), only Donald and Heyward are considered more interior than outside defensive linemen. Meanwhile, Mack's 10.5 sacks were tied for 14th among edge players, behind the likes of Ryan Kerrigan, Yannick Ngakoue, Julius Peppers, and Mario Addison.

So although their sack numbers are similar on the surface, Donald appears to have greater value in this area, since he produces more compared to other players at his position.

Mack did rack up a league-leading 78 total tackles among defensive linemen, while Donald was 50th. But tackle numbers can be deceptive, since they don't distinguish between a tackle that stops a rush for a 1-yard gain and one that ends a run 10 yards downfield. Donald, despite far fewer total tackles, actually had the same amount of tackles for loss as Mack (31) over the past two seasons while playing in two fewer games, according to teamrankings.com.

Dominating against the run is valuable, but Mack and Donald are in line to become the best-paid non-quarterbacks because of their impact on the passing game. Diving deeper into how Donald and Mack affect quarterbacks, the Rams superstar begins to separate himself from the competition.

According to Pro Football Focus, Donald recorded a league-leading 91 pressures (a sack, hit, or hurry of an opposing QB) over 483 pass-rushing snaps, giving him a rate of 5.31 pass-rushing snaps per pressure. Mack needed about 1.2 extra pass-rushing snaps to match Donald's output. Additionally, Donald's 91 pressures were 21 more than the next-best player at his position.

Mack comes out less favorably compared not only to Donald, but other elite edge players. According to PFF, Miller was the pressure leader among edge players with 84 on 447 snaps, five ahead of the third-place Mack. Miller racked up a pressure every 5.32 snaps, essentially matching Donald.

This tells us that Mack, despite his impressive performance, was a less efficient pass-rusher at a position that's historically dominated the NFL leaderboard in sacks and pressures.

Donald, on the other hand, excelled to a ludicrous degree for a player working primarily as a 3-technique rather than from an edge position. Miller is arguably the most talented pure pass-rusher in the league, and it's mind-boggling that Donald matched the linebacker's impact on opposing quarterbacks.

So who deserves the biggest Brink's truck?

Both Mack and Donald should exceed Miller's $19-million-per-season contract - signed in 2016, when the cap was $22 million lower than it is in 2018 - and break the $20-million barrier in annual salary for defensive players.

However, while Mack is a rare talent who excels equally against both the run and the pass, Donald is - like J.J. Watt before him - redefining the value of non-edge players thanks to his otherworldly production from the defensive tackle position.

The NFL has clearly realized the value of interior defensive linemen. Of the 25 highest-paid defensive players, 12 are edge players, five are cornerbacks, and eight are interior linemen, according to Spotrac. So while the league still values pure edge players most, it's become more open to rewarding game-changing interior players - and nobody changes a game like Donald. It could be argued that Mack is the slightly superior run defender, but Donald is the best pass-rusher in the league, regardless of position.

As the man quarterbacks fear the most, Donald deserves to be the NFL's highest-paid defensive player.

(Photos courtesy: Getty Images)