ENGLEWOOD, Colo. --While the Broncos' run defense has been off its pace of last year, by some measurements, its pass defense has managed to surpass its work during its memorable run to Super Bowl 50.

The Broncos again lead the league in pass defense, but this time also lead it in passer rating allowed. Opposing quarterbacks have compiled a rating of just 67.5 against the Broncos, a statistic made possible by holding foes to a league-low completion percentage of 53.8 and just 10 touchdown passes against 12 interceptions.

That figure is not only the best this season, but the best since Seattle held its 2013 foes to a collective passer rating of 63.4 -- 22.6 points below that year's league average.

Denver is the only team to hold opponents to fewer than five yards per pass play (4.90). No one has allowed fewer pass plays of 20 or more yards; the Broncos have given up just 29 -- one every 16.7 pass plays. (The league average is once every 11.5 pass plays.

They lead the league in sacks (40), and only one other team (Buffalo) has a better sack rate than the Broncos, who bring down opposing quarterbacks once every 13.1 pass plays.

Everything adds up to a pass defense that, when compared with the league average, is among the best of recent vintage.

But with a 67.5 rating representing the league's best pass defense by that statistic, it shows just how much the standards have changed in the sport over the decades.

In 1978, the first year in which passing rules were liberalized, the league average rating was 65.0. But even as recently as 2003, the league's average quarterback rating remained in the 70s, when it was 78.3.

This year, a league-average rating is 89.4 -- a slight drop from the 90.2 rating of the 2015 season that was an NFL record. But the Broncos' pass defense this year has limited foes to a rating 21.9 points this year's league average -- an over-average figure that currently ranks sixth-best of any team in the last 25 seasons, and 14th since the 1978 rules changes.

This isn't a perfect encore for the defense following its memorable 2015, and if the Broncos cannot rally for a return to the postseason, the numbers will be a bit hollow. But they do reveal a defense that remains elite -- and should stay that way in 2017.