LAKE FOREST, Ill. -- The statistical tale of the tape over the past three years between superstar defenders Aaron Donald, of the Los Angeles Rams, and Khalil Mack, of the Chicago Bears, does not tell the entire story.

What cannot be disputed is Donald remains a force of nature on defense.

The 30-year-old Rams defensive lineman is annually voted by his peers as one of the top-10 players in the league. For good reason. From 2018 to 2020 alone, Donald racked up an astonishing 46.5 regular-season sacks on the way to winning two of his three NFL Defensive Player of the Year awards.

The Bears strongly believe Mack still plays on Donald’s ultra-elite level, even though -- on paper -- Mack’s overall production has cooled the past two seasons.

The Bears and Rams open the regular season on Sunday night at SoFi stadium (8:20 p.m. ET, NBC).

Mack, who won NFL Defensive Player of the Year honors in 2015, failed to crack double-digits in sacks in each of the past two years. The last time that happened -- prior to 2019 and 2020 -- was Mack’s rookie season with the Raiders in 2014.

Mack is routinely the focus of the opposing offense's protection plan, but the perennial Pro Bowler went through unusually -- for him -- long stretches when he did not reach the quarterback. For a player of Mack’s stature, the lower-than-expected numerical output raised eyebrows. After all, the Bears guaranteed Mack $90 million, and he ate up $26.6 million in salary-cap space last year. The Bears managed to lower Mack’s cap number to $14.646 million in 2021, but it balloons to $30.150 million in 2022.

What was sometimes lost in the shuffle last year was that Mack, who played in all 16 games and the playoff loss to the New Orleans Saints, routinely popped up on the injury report with a bad shoulder. Little was revealed publicly about Mack’s condition, but the shoulder problem was real.

“I’m not blaming anything on anything, you know what I’m saying,” Mack said at training camp. “When I’m out there, I’m doing whatever I can to help the team win. That’s ultimately the kind of guy you got with me.

“For the most part, it is what it is. But I want to keep talking about as if it had too much of an affect. But it is what it is at the end of the day. Everybody in the building knows what it was. It is what it is.”

Whatever the extent of Mack’s bum shoulder, the injury is clearly behind him.

Mack reported to camp in great shape and stayed healthy throughout the preseason. Bears coach Matt Nagy occasionally gave Mack and other veteran players breathers, but for the most part, Mack practiced virtually every day and showed no signs of injury or discomfort until being limited at practice with a groin injury Wednesday.

“I think Khalil had a real good training camp,” Bears defensive coordinator Sean Desai said.

“He's been out there, he's been healthy and he's been great. And so we like where he's at now,” he added.

“He only knows one speed and that’s what makes him great,” Bears safety Tashaun Gipson said. “That’s why playing with a guy like that is just -- you can never really take advantage of playing with great players like that. ... Just a humble dude. He’s one of the guys, man -- for sure Hall of Fame. But he’s one of the guys, man.

“That’s the beautiful thing. He practices like he’s a rookie. Like it’s Year 1 or Year 2 for him. That’s a testament to the type of person he is, type of leader he is, type of player he is. And that’s why the defense feeds off him. If Mack can go 100%, why can’t anyone else on the defense?”

As Bears veteran defensive lineman Angelo Blackson put it, “the guy [Mack] is a beast.”

“Watching him go out and practice and perform, it definitely, it wears off on you and it lets you know how you need to work,” Blackson added. “That’s just been the biggest for me is going out and watching him and trying to bring the same intensity.”

Nagy, who met the media every day at camp, answered only a handful of questions about Mack over the span of month.

The reason: Not much needed to be said.

The confidence level inside the building that Mack is primed for a huge year is sky high.

Nagy believes most around the league share the same sentiment.

“These offensive coordinators understand that every day they walk in on a Tuesday for the game plan, they always highlight this guy or that guy,” Nagy said. “This guy can not affect or wreck the game. Khalil is that guy."