On the whole, sack rates are on a steady, if inconsistent decline. Since the sack became an official NFL statistic in 1982, the sack rate peaked in 1984, with one every 11.91 pass plays. Undulations followed over the years, but the sack rate has been one every 15 or more pass plays every year since 2006, and has not been more frequent than one every 14.0 pass plays since 1998.

The gradual drop-off is not because the pass rushers are worse or the offensive linemen are better. It’s because of myriad other factors, including the increased effectiveness of mobile quarterbacks, the prominence of quick timing offenses, the increased penalties for late or helmet-to-helmet hits that force defenders to throttle back, and the overall empahsis on passing which changes how teams utilize this aspect of their offenses, and ensures that pass rushing is not just about “pinning the ears back” and attacking.

Through six weeks, the NFL is on pace for its lowest sack rate: one every 17.7 pass plays. Just 5.65 percent of all pass plays this season end in sacks. The effect on other passing metrics is clear: league-wide completion percentage (63.3 percent) and yards per pass play (6.51) have never been better in the sack-as-official-stat era.

That makes the Broncos’ recent pass-rush performance all the more notable. After a slow start in the first two weeks — five sacks, giving the Broncos one every 20.0 pass plays — the Broncos have improved to one every 12.2 pass plays in the last three games, two of which were against mobile quarterbacks: Seattle’s Russell Wilson and the Jets’ Geno Smith.

Sunday, the Broncos averaged one sack every 10.75 pass plays, and they were the product of complementary football.

On the first, with 7:35 left in the second quarter, good downfield coverage prevented Smith from having …read more