They have a Defensive Player of the Year (Mack) and a Super Bowl MVP (Miller) between them and each is still considered to be in his pass-rushing prime.
Peel the proverbial onion and they are different sorts of players, with different skill sets and personalities, but each has a common layer of humanity underneath.
"We like each other, for sure," Miller said. "Khalil, that's my guy, he's great. He's been one of the best, a great defensive player since he came into the National Football League. I thought he was untradable when the Raiders traded him, but I'm always glad when a guy like Khalil gets what he deserves. The guy is great."
As Miller's Broncos and Mack's Bears prepare to take the field Sunday in Denver (4:25 p.m. ET, Fox), let's look at what makes them go.
What makes them great
Richard Smith was Miller's first position coach after the Broncos took him with the second overall pick ofthe 2011 draft. Smith often said when Miller's maturity and knowledge of the game matched his physical abilities and love of playing, "you would have one of the best, the total package."
Now in his ninth NFL year, Miller says he has streamlined "what's important to me, what I need to worry about, leaving a legacy of what I did to help my team win." He's 30 years old but says he feels like "a young guy."
Former Broncos linebacker DeMarcus Ware, whom Miller counts as one of the most important on-field mentors in his career, has always said you have to "look behind the smile because that's where the sacks come from with him. All that goes on behind the smile."
It's something Miller sees in Mack.
"[Mack] is just a really good player, from day one in the league, and I just respect good players," Miller said. "I've been around the league nine years now and the best compliments you can get are from the guys in the league and I always try to keep it real and really, he's really good."
Bears starting left tackle Charles Leno knows. He battles Mack at practice on a daily basis. In the summer of 2018, he also got an up-close look at Miller as the Bears traveled to Denver for two days of joint practices prior to a preseason game.
"They're both explosive players and probably the best at their job -- the top two edge rushers in the league," Leno said. "But there's a big difference between the two. Von is more of an outside rusher. Khalil will do a lot more power moves. Von will just burn you off the edge with speed. Those guys are just really high-level players. As an offensive lineman, you have to be ready because they are both game-changers."
Mack singles out Miller's ability to "bend the corner, like nobody else in the league" as his signature move.
Miller has a gifted and cultivated ability to turn speed and quickness into power. And when he gets a sliver of daylight to the outside shoulder of the tackle he has the flexibility to dip underneath the blocker's hands and shoulders to get the advantage.
"And he can dip all the way down and still keep his momentum going, it doesn't cost him speed to the quarterback," former Broncos guard Mark Schlereth said. "That's rare, really rare."
"I think about my hands sometimes, setting up things for later in the game," Miller said. "But in the moment, you're just trying to get to the quarterback, speed, power, whatever, you just want to get to the quarterback, make a game-changing play."
Mack's move? He's coming right at you. "He's got all that power," Miller said. Tackles who have faced Mack call it "the long arm" -- the way Mack can create leverage with just one arm, to increase his reach to keep the blockers' hands off of him, as he moves forward.
"That's how he creates space," Schlereth said. "And space wins in the rush."
The impact of impact players
Sacks will always be the prize for pass-rushers. But Ware, for one, has always said the best all-around edge players are the ones who find a way to "do the most, to affect things the most, even when the sacks don't come. You're not always going to sack quarterbacks, but you can always play your best and do things to win."
Both Mack and Miller finished Week 1 without a sack in losses.
"If I don't get a sack, I'm going to be upset, that's just how it is," Miller said. "Y'all been knowing me for nine years, if I don't get a sack and we lose on top of that too, that's a double loss. That's my job and I like to get my job done."
But those around them say there is so much more to their games.
"Khalil played as well as I've ever had a guy play in a game," Bears outside linebacker coach Ted Monachino said of the loss to the Packers in Week 1. "I know he would've preferred to impact the game more, but from a down-to-down basis he impacted 31 out of the 34 plays he was in, in our favor. And that's 88 percent, that's a really high percentage. So thrilled with the way he played. He's an eyelash away from making five plays in that game and those five plays eventually got finished by another player on our team. ... I know that as people are watching tape they're seeing the same thing."
Broncos coach Vic Fangio offered a similar review of Miller's Week 1 effort, but said the Broncos' failure on first and second downs limited Miller's ability to turn it loose on third down.
"In a lot of ways he played really good the other day," Fangio said. "He played the run good, he was physical, he played tough, he anchored his side pretty damn good. ... Again, I know everybody wants to see the sacks and the hits and whatnot, he didn't really have much of a chance."
"Mack and Von are very similar," Bears coach Matt Nagy said. "Very, very similar. We in Kansas City, when I was there, we had to go against Miller for a bunch of years and you always got to know where he's at. He's savvy, he's smart, he's quick with his hands, he has these ninja-like moves that just are hard to stop. But when you have a guy that is as good of a player as Von Miller is, you have to know where he's at at all times."
What does the future hold?
As long as there are quarterbacks to be sacked, there will be those who can chase quarterbacks down.
Miller convenes his Pass Rush Summit each summer and says Mack is one of his first invitees. Miller believes the summit is the future of the "craft of pass-rushing," and he said the 28-year-old Mack is a big part of that. Miller looks at Mack and says, over and over again, the "sky's the limit, he's that kind of player."
Mack's contract with the Bears runs through 2024 and guarantees him $90 million as his best football is probably ahead of him, given what he's already shown.
Because of his holdout in Oakland just over a year ago, Mack didn't even have the benefit of an offseason program or training camp when he arrived in Chicago, and he still dominated with 12.5 sacks, six forced fumbles, 11 tackles for loss and a pick-six.
His 2018 Bears debut against Green Bay (three tackles, one sack, one pick-six, one forced fumble, one fumble recovery, one tackle for loss) ranks among the greatest individual defensive performances in team history.
"I didn't know a lot about him [when the Bears traded for Mack], other than I knew he was a good player," said Fangio, who as the Bears' defensive coordinator last season has now coached both players. "When he came out of college, we were drafting very late in the first round in San Francisco at the time, so they said don't even bother watching him, so I didn't watch him as a collegian. And with him in Oakland and me in the NFC I didn't really see him play a lot. And then when we got him, and it was just after a few days it was like holy s---."
The Broncos, too, believe there is plenty of elite football in Miller -- Fangio made it clear when he was hired, Miller had "more to give." Miller has embraced the push his 61-year-old head coach has given him. The Broncos will face a decision about Miller's future at season's end.
His contract runs through 2021, but the Broncos have an option that would have to be exercised in March that engages $6 million in guarantees for next season. But that's all discussion for the grown-up table months from now.
Now it's about quarterbacks, about sacks, about wins.
"Game-changing plays, helping your team win, leading my guys, that's the job," Miller said. "I like my job. Khalil, he likes his job too."
Miller or Mack: Who would you start a franchise with?
The NFL Live crew is forced to make a choice on who would be a better player to start a franchise with between Khalil Mack and Von Miller.