The 2015 Denver Broncos had the best defense in the NFL. They led the league in total yards allowed, yards allowed per play, yards allowed per drive, and points allowed per drive. They also led in more advanced statistics like Pro-Football-Reference's expected points contributed and Football Outsiders' defensive DVOA (Defense-adjusted Value Over Average, which adjusts performance for down, distance, and opponent). They were the eighth-best defense in Football Outsiders' entire database, which goes back to 1989. Basically what we're trying to say here is: they were really damn good.

So when a player on another team says that his defense can be as good as the 2015 Broncos, he's making quite a claim. And that's exactly what Raiders star Khalil Mack did on Saturday.

"We can be that good. If you look at that Broncos defense, they're one of the best defenses in NFL history last year," Mack said, per Yahoo!'s Shutdown Corner blog. "They did a lot to make the quarterback uncomfortable. We can do those types of things and still put our own little twist on it."

Mack is certainly correct that the basis of that Broncos defense was making the quarterback uncomfortable. Behind the relentless pressure of Von Miller and DeMarcus Ware, Malik Jackson and Derek Wolfe, Shaq Barrett and Shane Ray, Sylvester Williams and Antonio Smith, the Broncos racked up a league-leading 52 sacks. Their 8.1 percent adjusted sack rate (per Football Outsiders, sacks plus intentional grounding divided by dropbacks, adjusted for down and distance) led the league, as did their 42.8 percent pressure rate (sacks plus hits plus hurries divided by dropbacks, per an analysis of Pro Football Focus' tracking data).

The Mack-led Raiders did not fare quite as well in those categories. They finished the season with 38 sacks, just slightly more than the league average of 37.1. Their adjusted sack rate was actually slightly below average at 5.9 percent, while their pressure rate of 34.0 percent ranked 21st in the NFL.

Oakland spent the 2016 offseason making significant upgrades to its defense, though. The Raiders signed Bruce Irvin away from the Seahawks to rush the passer opposite Mack. They added former Chiefs corner Sean Smith and former Bengals safety Reggie Nelson in free agency, then drafted West Virginia's Karl Joseph, arguably the draft's hardest hitter, with their first-round pick.

That's a whole lot of talent, and it should help the Raiders make a significant improvement on defense. It just might not happen all at once.

"You want it to happen right away, but we have to know that coming together takes time," Mack added. "We have the talent now, and we can disrupt the way they do and be that dominant if we max out and put it all together."

Will the Oakland defense be better? Most likely. Will it be as good as the 2015 Broncos? Probably not. But it's always good to aim high.

Khalil Mack has high hopes for the 2016 Raiders defense. USATSI