Breaking down three key matchups with a deep statistical dive from the Detroit Lions vs San Francisco 49ers
When this rematch of last year’s NFC Championship between the Detroit Lions and San Francisco 49ers was announced during the offseason, it seemed destined to have playoff implications. While the Lions exceed most preseason expectations, at 13-2, the results of Monday Night Football will have little to no impact on their playoff fate—that’ll have to wait for Week 18 Sunday Night Football against the Minnesota Vikings. On the other end, the 49ers’ are already eliminated from the postseason, so they also have little to play for beyond pride.
Despite the lack of playoff ramifications, coach Dan Campbell already told the media on Monday last week that “we’re bringing everything we’ve got into this game” so the expectation is that the Lions will be out of their cage looking to tear apart the gold prospectors at Levi’s Stadium. Additionally, Amon-Ra St. Brown also said, after the Bears game, that he wanted the win (against the 49ers) and that last season’s NFC Championship Game was up there with the worst loss in his football career. So expect the Lions players and coaches to be out for revenge, similar to how they were against the Dallas Cowboys in Week 6.
Note: Unless otherwise indicated, all statistics were made available via NFL Pro or FTN Fantasy.
Purdy passive passes
The 49ers, while not as injured as the Lions, have been one of the most injury-riddled teams in the NFL this season. One of the most impactful injuries they have suffered was to wide receiver Brandon Aiyuk (a player seared into Lions fan memories for all of the wrong reasons). Since Week 8, Aiyuk was injured in Week 7, Purdy has had some shortcomings in throwing past the sticks. Aiyuk was the offense’s best downfield ball winner and they’ve been lacking in their ability to stretch the field since then.
In that span, on passes of 15+ air yards, Purdy has only attempted 4.7 pass attempts/game which is 32nd (out of 42 qualifying quarterbacks) as he’s been hesitant to pull the trigger. Below is a list of several other of Purdy’s 15+ air yard passing metrics (since Week 8):
- 45.5% completion percentage (17th)
- 1 passing touchdown (tied 26th)
- 15 passing 1st downs (tied 23rd)
- 89.3 passer rating (19th)
- 45.5% success rate (19th)
- 0.42 EPA/dropback (20th)
- 59.0% DVOA (19th)
Purdy has turned into barely a borderline top-20 quarterback when trying to stretch the field without Aiyuk and that should play into the Lions’ hands.
The Lions’ defense has been admirable against passes of 15+ yards. Defensive coordinator Aaron Glenn’s unit has allowed a 39.5% completion percentage (11th), a 39.5% success rate (10th), have 24 pass break-ups (9th), and a 0.27 EPA/dropback allowed (14th). They’ve been even better when it comes to such passes in the end zone, allowing only one touchdown and forcing three interceptions on 11 such attempts.
Adding to the equation that the 49ers may not be able to stretch the Lions defense is the fact that the 49ers, due to a litany of injuries, very well could be tapping into their third- and fourth-string offensive linemen at left tackle and left guard, while their right tackle is listed as questionable.
Purdy has been passive in throwing anything other than short passes, the Lions have defended longer passes well, and the 49ers’ offensive line might only allow for a quick and short passing game which means hopefully the lack of a deep passing threat will allow for the Lions defense to play heavy in stopping the run.
Glenn’s Blitzkrieg Bop
Even without, Aiyuk, Purdy has been productive when facing the blitz. Since Week 8 against the blitz, Purdy has a 67.7% completion percentage (9th), 8.4 pass yards/attempt (10th), five passing touchdowns (7th), a 112.7 passer rating (9th), a 60.0% success rate (2nd), and a 0.21 EPA/dropback (10th). Purdy has managed to handle the blitz well, with decisive decision-making, even in a down year for the Niners offense.
While Purdy has succeeded against the blitz this year, the Lions will still rely on getting after the quarterback by bringing additional bodies for a few reasons.
As previously noted, the 49ers’ offensive line depth has been tested with injury and what better way to test their chemistry than by attacking inexperienced and unfamiliar players? The Niners may be starting players such as Charlie Heck (signed off of the Arizona practice squad Thursday), Nick Zakelj (34 career snaps), and Sebastian Gutierrez (3 career snaps). Not only may those inexperienced offensive linemen potentially be in charge of protecting Purdy but so will their rookie running back Isaac Guerendo and fifth-string running back Patrick Taylor who are replacement-level running backs in pass protection. That is too many cogs functioning on the same page to not lead to communication issues.
The Lions defense since Week 7, following Aidan Hutchinson’s Week 6 injury, the Lions have blitzed on 141 dropbacks or 12.4 dropbacks/game (both 4th most over that time period). When blitzing, in that time span, the Lions defense has allowed a 52.4% completion percentage (5th), 6.8 passing yards/game (10th), only a 39.5% success rate, and -0.18 EPA/dropback (4th). They are however bottom five in the NFL in pressure rate (30.5%) in that span.
The Lions, even without Hutchinson and without consistently getting to the quarterback, have been one of the best defenses when blitzing and will look to do so, selectively, against the novice 49ers’ pass protectors and Purdy.
Off tackle
One area that the Lions exploited well in the NFC Championship Game last season, was running outside of the tackles. This season the 49ers defense has been one of the worst in containing and stopping outside runs. They struggled with it down the stretch last year but are even worse this year given a combination of scheme regression and talent reduction on their defensive line.
The 49ers run defense, against outside runs, has allowed a +0.16 EPA/rush (32nd), 5.6 yards/rush (29th), +0.92 rushing yards over expectation/attempt (27th), 46.8 success rate (30th), 2.02 yards before contact/attempt (26th), and 3.55 yards after contact/attempt (t-27th). They’ve devolved into one of the most susceptible run defenses off tackle in the entire league.
Meanwhile, just as he had success running off the backsides of Penei Sewell, Taylor Decker, and the tight ends in the NFC Championship Game, Jahmyr Gibbs has had success this season and should continue to do so against the 49ers. Against outside runs, Gibbs has generated seven rushing touchdowns (t-3rd), 5.3 yards/rush (6th), a +0.04 EPA/rushing attempt, a 43.6% success rate (8th), 19 10+ yard runs (6th), and 45 15+ miles/hour runs (6th).
Gibbs has been one of the best running backs in football this season and that includes on outside runs so look for the Lions, and offensive coordinator Ben Johnson, to scheme runs off tackle to gash the 49ers en route to a convincing victory.
