The NFL is in the midst of an offensive era.
Quarterback play is the best it’s ever been and points are being scored this decade at a rate that hasn’t been seen since the 1960s.
The 2019 season has been par for the course. High-flying offenses have been the theme, while defenses have rendered useless – that is, unless they’re facing the woefully inept Washington Redskins, Miami Dolphins, New York Jets or Cincinnati Bengals.
Despite the abundance of offensive dominance, two defenses have risen to the challenge and managed to somehow produce excellent results – not just within the context of this high-scoring era, but on a deeper, historic level.
The New England Patriots (8-1) and San Francisco 49ers (8-0) are allowing just 10.9 and 12.8 points per game, respectively, on the way to the best records in their respective conferences heading into San Francisco’s showdown with the Seattle Seahawks on Monday night.
Since the 2010 season, no defense has sustained those numbers over the course of a season. The closest was the 2011 Pittsburgh Steelers, who allowed 14.2. In this offensive period, nobody has even come close to touching the dominance of these defenses.
The 2019 Patriots are on pace to allow the second-fewest points per game since 1980, behind only Ray Lewis and the 2000 Super Bowl champion Baltimore Ravens (10.3). The 49ers aren’t far behind over that four-decade time period, tied for 11th in points allowed per game.
These historical rankings are where the similarities end, though. The Patriots and 49ers have employed extremely different schemes with contrasting personnel this season – a striking representation of the diversity of systems that can succeed in the modern NFL.
As seen above, New England is the most man-heavy team in the league. Also note that former Patriots coaches Matt Patricia and Brian Flores lead the next heaviest man-coverage teams, the Lions and Dolphins, respectively.
That’s not news to people who have been watching closely – over the past few years the Pats’ coverages have skewed heavily toward man-to-man. In Super Bowl LIII they actually flipped that script, stunning the Rams with a surprisingly high percentage of zone plays after playing more man coverage all year.
On the other hand, the 49ers play the second heaviest zone scheme in the league, behind only the Carolina Panthers. They lead the league in Cover 6 plays, and also play a huge amount of Cover 3 and Cover 4.
Of course, what makes these respective coverages work is the personnel. For San Francisco, defensive backs Richard Sherman and Ahkello Witherspoon have excelled in zone, while New England features Stephon Gilmore – by many measures the NFL’s best cornerback this season.
Another key to the teams’ performance has been the play on the defensive front. The 49ers and Patriots are generating their share of pressure, averaging 3.75 and 3.56 sacks per game – good for second and fourth in the league, respectively.
But again, they’re managing to create havoc in the opposing backfield in vastly different ways.
As seen above, the 49ers line up with just four defenders on the line more than any other team in the league. They rely on that front four to generate pressure – and they’ve delivered.
Stats Perform calculates the expected rate of pressure for each defensive line position among players with more than 70 pass-rush opportunities (dropbacks where the quarterback holds the ball for longer than 1.9 seconds and not including run-pass option plays and bootlegs). For edge rushers, the expected pressure rate is 12%. For defensive tackles, it’s 11.5% and for nose tackles, it’s 9.7%.
San Francisco’s edge players have been especially effective at getting to the QB, blowing the expected pressure rate out of the water. Nick Bosa leads the league in pressure rate – 21.9% better than the expected rate. On the other side of the line, Arik Armstead has a pressure rate 5.8% higher than the expected average and Dee Ford, who rotates in, ranks second in the NFL with a rate that’s 17.1% higher than the average.
DeForest Buckner gives San Francisco another difference-maker on the inside as he leads the league with a pressure rate that’s 12.1% better than the expected mark for defensive tackles.
In the video below, Bosa gets matched up on a tight end against the Browns in Week 4 and almost gets to Baker Mayfield, who forces a throw into the deep Cover-4 zone manned by Sherman.
The Patriots, however, don’t have the impact pass rushers that the 49ers have, and often look to six- or seven-man pressures to disrupt the QB. Of course, this works because New England has some of the league’s best man-coverage corners in Gilmore, Jonathan Jones and Jason McCourty, and two elite safeties in Devin McCourty and Patrick Chung.
Jamie Collins and Dont’a Hightower lead a mobile group of linebackers capable of either blitzing the QB or shadowing running backs and tight ends in pass coverage.
That’s not to say these impressively engineered and talented defenses don’t have their weaknesses. In Week 9, the Patriots struggled in a 37-20 loss to the Ravens and the 49ers were exposed in a nervy 28-25 victory over the Arizona Cardinals.
Both had trouble stopping mobile QBs and the running game overall. Baltimore’s Lamar Jackson ran 16 times for 61 yards and two touchdowns, while Mark Ingram and Gus Edwards combined for 22 carries for 142 yards and a touchdown. Arizona’s Kyler Murray scampered for 34 yards on five rushing attempts and Kenyon Drake rushed for 110 and a score on 15 carries.
Perhaps establishing the run is the key to breaking the Pats and 49ers?
Our analysis reveals that might not be the long-term solution. Stats Perform’s proprietary data measures run disruptions, a measure of how often a defender beats his block to the point where he can control more than one gap or penetrate through the blocking scheme. Similar to our rate of pressure calculations, run disruptions are represented as a percent above or below the expected value for a specific position.
The Patriots and 49ers rank 11th and 12th, respectively, in rate of run disruption, with each team having a few particular standout players. San Francisco’s Armstead has a rate 11.4% better than expected, while Ronald Blair and Bosa come in with rates 5.8% and 1.3% better. New England’s strength is on the inside, where Lawrence Guy has a disruption rate 5.0% better than the expected value and Danny Shelton is 0.4% above average.
Likely the more accurate takeaway from Week 9 is that both defenses were simply caught off-guard by two unique offenses that were run by two dynamic dual-threat QBs. The 49ers will try to pass another test when they visit Baltimore on Dec. 1, while the Patriots face Deshaun Watson and Patrick Mahomes in back-to-back weeks in December.
Should San Francisco and New England continue their eye-opening performance on that side of the ball, we could witness an unlikely second straight defense-dominated Super Bowl of this high-scoring era.
Advanced analytics and data analysis provided by Stats Perform’s Kyle Cunningham-Rhoads