The Falcons didn’t have a good defense for Quinn’s first four seasons as coach. They may have had the worst defense in the league in 2018, though injuries were a factor. Quinn took over as coordinator, the defense is healthier and the Falcons still are on track to be among the worst again.
There’s no reason to believe the Falcons can duplicate what the 2015 Chiefs and 2018 Colts did. Those teams weren’t good on defense the season before and to begin the next season. They ended up ranking among the top units in the league during their turnaround seasons.
The indispensable Football Outsiders computes an efficiency metric that accounts for every play and adjusts for situation and opponent. The 2015 Chiefs ranked sixth and the 2018 Colts were 10th. The Chiefs were ranked 19th in 2014 and the Colts were 27th in 2017.
The 2018 Falcons ranked 31st in the Football Outsiders defensive metric. They rank 29th through six games this season. Tampa Bay, which had last season’s worst-ranked defense, now ranks 17th. Nothing about the play of the Falcons defense so far, or Quinn’s five-year tenure, suggests it can make a similar leap.
My view is that the Falcons’ problems are all connected to a weak pass rush. Pressuring the quarterback could mitigate some of their problems in coverage. The Falcons rank last in the NFL by a wide margin in third-down percentage allowed. That’s mostly because opponents are having little trouble passing in those situations.
According to Sharp Football Stats, the Falcons rank 31st in passing success rate allowed on third down and 22nd in run success rate allowed (defined as gaining 40% of yards-to-go on first down, 60% on second down and 100% on third and fourth down). The Falcons have been good against the run overall. They rank ninth in both rushing yards allowed per play and run success rate allowed
When opposing QBs pass against the Falcons they don’t have to worry much about getting sacked. Football Outsiders’ sack rate is adjusted for down, distance, and opponent and includes intentional groundings. This season the Falcons rank 32nd in adjusted sack rate. Their rankings in Quinn’s four previous seasons as coach: 32nd, 24th, 19th and 25th.
Probably the biggest indictment of the Quinn-Thomas Dimitroff “co-team builder” era is their failure to field a defense that can rush the passer. Like his predecessor, Mike Smith, Quinn often downplays sacks while citing overall QB pressures. He talks about a defense can be effective by moving the quarterback “off his spot” without sacking him.
There's some validity to that view. Pro Football Focus data for the past ten years shows that quarterbacks who are pressured see an average decrease of 32 points in passer rating on those throws. But it also concluded that a sack is about 25 times more valuable than pressure without a sack (hurried or hit).
That makes sense. A quarterback who is moved off his spot still can scramble for runs or make throws. Instead of losing yards on a sack they can gain yards or at least throw the ball away to make down-and-distances more manageable. That’s happened to the Falcons plenty this season.
Cardinals quarterback Kyler Murray consistently escaped pressure to extend plays. Jacoby Brissett (Colts) and Deshaun Watson (Texans) did the same. In Week 8 the Falcons will face Seahawks quarterback Russell Wilson, who is among the best QBs of all-time at making plays outside of the pocket.
The Quinn-Dimitroff Falcons haven’t invested many of their resources in the pass rush. They selected two edge rushers in the first round of two drafts (Vic Beasley and Takkarist McKinley) but none at all in the other three drafts. The most guaranteed money they spent on a free-agent edge rusher was $7.5 million for Derrick Shelby in 2017.
The Falcons don’t sack the quarterback often. They never have with Quinn as coach. That’s a big reason why they’ve never been good on defense. The defense is bad again this year with no sign of a turnaround.
And that’s why the 2019 Falcons, unlike the 2015 Chiefs and 2018 Colts, won’t recover from a 1-5 start to make the playoffs.