Are Bad NFL Defenses Breaking Win Probability Models?


sara.ziegler (Sara Ziegler, sports editor): Week 7 of the NFL season gave us a LOT to unpack: The Atlanta Falcons lost yet another game they seemed to have sewn up, while the Dallas Cowboys lost another quarterback during a truly dreadful defeat at the hands of the Washington Football Team. And who could forget the best tackle ever made by a 20-yard line?

But we start with the Sunday night game, which pitted the always-living-dangerously Seattle Seahawks against the who-knows-what-you’ll-get-from-them Arizona Cardinals. This game had a little of everything: In the overtime alone, we saw a missed field goal, a touchdown called back on a holding penalty, an interception on the very next play, and then field goal redemption!

neil (Neil Paine, senior sportswriter): I tuned in after the World Series game just in time to see the end!

(And wondered how the hell Arizona even forced OT to begin with, given the score when I periodically checked it earlier…)

Salfino (Michael Salfino, FiveThirtyEight contributor): The game featured the most combined yards in a regular-season game since 2013 (though Super Bowl LII had more). Neither team could play defense. The Seahawks haven’t played defense all year.

Seattle’s defense is quarantined.

joshua.hermsmeyer (Josh Hermsmeyer, NFL analyst): I guess this is where I point and laugh at win probability models, again.

neil: Ya gotta watch out for that 0.1 percent.

Salfino: There is a nerd civil war over win probability models, and I’m here for it. Where are you on this, Neil? Sara?

sara.ziegler: I mean…

neil: I think they could probably use an audit if 0.1 percent things are happening every week.

sara.ziegler: I think that we’re probably looking at them in the wrong way.

Salfino: Isn’t the idea that in games like this, with this score and time, team X wins Y percent of the time? It seems like there are too many independent variables for real back-testing, though. I feel like they overpromise.

joshua.hermsmeyer: To be fair, I think they mostly get it right, and we focus on the outliers. But the entire point is to highlight the outliers, as far as I can tell. And this year in particular, it hasn’t been great.

sara.ziegler: I think we want to jump on the models when the unlikely thing happens, but I like to use those models to see just how unlikely the thing was and then enjoy that! Instead of getting mad that the unlikely thing happened. (But yeah, those should maybe be redone in this era of offense.)

neil: Is one solution just to add more uncertainty for the defensive team holding a lead? Since defenses appear to be struggling to, like, do that?

Salfino: Defenses are so bad you can’t even not score on purpose against them.

neil: OMG. Falcons … why???

The headline on this story was great: “Falcons find a new way to lose: by scoring a touchdown.”

Salfino: Is Atlanta the best or the worst? ESPN’s Stats & Information Group said this was the Falcons’ third loss off the season when they had a win probability of at least 98 percent, “the most by a team in the last 20 seasons.”

Todd Gurley looked like he was failing a sobriety test when he fell into the end zone. It’s the new Butt Fumble, except it actually determined the outcome of a game.

And how ironic was it that the Falcons blew the game to the Lions, another team known for blowing leads. I guess this was inevitable. The best part was the Lions defenders celebrating the TD.

sara.ziegler: That was quite the image.

joshua.hermsmeyer: I very much enjoyed Adrian Peterson’s 11-carry, 29-yard rushing performance. The Lions’ rushing attack was third-worst so far this week (-0.22 expected points added per play), ahead of just the Eagles and Texans. And they still won.

neil: It’s so crazy because this season, teams have scored a TD on just 26 percent of drives; even the best teams haven’t cracked 40 percent. Yet somehow, there is always a situation where a defense needs to stop a team from driving the length of the field with a minute left, and it feels like they fail more often than not!

Salfino: It’s like every defense has Edwin Diaz closing.

neil: Ooooof

sara.ziegler: Mets reference in the NFL chat!

neil: I think teams should pretend they’re down 6 with a minute left on every drive. Would lead to the best offense ever.

joshua.hermsmeyer: Love it, Neil, and pretend your kickers retired before the game.

neil: Josh, we’ll get that if Daryl Morey takes over the Texans.

sara.ziegler: LOL

Salfino: But aren’t the defenses so awful? Sara is right, I think, that it’s screwing up the modeling. Seattle is on pace to give up 7,667 yards, 600 more than the record set by the New Orleans Saints in 2012. And somehow, they are a Super Bowl favorite. (I reject that; defense has to matter A LITTLE.)

There are three winning teams in the all-time bottom 10 in yards allowed — the 2011 Packers, 2011 Patriots and 2018 Chiefs. None won a Super Bowl.

joshua.hermsmeyer: That’s a stat!

Salfino: Josh, do you think that Seattle is a Super Bowl contender despite that defense?

joshua.hermsmeyer: Mike, yes, I think that whatever it is we think we know about the Hawks defense right now is likely wrong. I suspect they are not good but probably can put together a stretch of average play.

Salfino: I guess I agree, if they face the right offenses. But the Cardinals are hardly an offensive juggernaut.

sara.ziegler: The Seahawks just need D.K. Metcalf to be a true two-way player, and then they’ll be fine:

neil: And on the flip side, now that Arizona is 5-2, do we all owe Kliff Kingsbury an apology?

Salfino: Kyler Murray is setting fantasy on fire. He has a rushing and passing TD in six of his team’s first seven games, the first player ever to do this. But do we think he’s great? I don’t.

joshua.hermsmeyer: I think he’s the best-performing No. 1 overall pick from 2019! It was a good week for former No. 1 overalls: Baker Mayfield threw for five TDs against the Bengals.

neil: Kyler is fifth among 2020 QBs in EPA, for what that’s worth.

sara.ziegler: Why don’t you think he’s good, Mike?

Salfino: I think he’s good but not an MVP-level player. He’s an insanely good runner, though. I think you can defend this offense.

But in fairness, it looks like you can defend Patrick Mahomes this year, too, and we know Mahomes is great. Ironically, in a year when defense is at an all-time worst, Kansas City has problems … on offense.

joshua.hermsmeyer: Agree with you that Mahomes doesn’t look the same, Mike. The past four weeks, he ranks 17th in QBR. What do you think is wrong with him?

Salfino: It seems like defenses are making him play small ball, and he doesn’t like that.

sara.ziegler: He didn’t play well on Sunday, but that was in the snow … and his team won by 27.

Salfino: Good point about the weather, Sara, but the Broncos had over 400 yards. And Kansas City went 0-for-8 on third down.

neil: It’s funny because Chiefs receivers are actually getting more average separation these past three games — 4.26 yards vs. 3.82 — than they did last season.

But Mahomes is undershooting his expected completion percentage by more.

Salfino: Is that separation stat meaningful, Neil? I can’t get anything correlative out of it.

neil: There’s probably some selection bias in the sense that it only measures throws that get made, not how “open” everyone is on all routes.

joshua.hermsmeyer: Agreed, Neil. Also, average separation really obscures some important things like route mix.

neil: But it is telling in the sense that the difficulty of Mahomes’s throws (to the extent we can measure that) hasn’t changed almost at all.

joshua.hermsmeyer: Yep, and his average depth of target isn’t super low; it’s still in the 8s.

Salfino: It’s weird that Mahomes is not even the best deep thrower now in his own division.

That’s Justin “Marino” Hebert, of course.

sara.ziegler: 🤣

neil: That would be true if Tyrod Taylor were still starting too.

(Poor Tyrod. He has had the unluckiest QB career I can think of.)

sara.ziegler: Ugh, so true.

Let’s talk about another quarterback, one who’s really struggling: Cam Newton. The Patriots have some serious problems right now.

Salfino: Remember when Cam was the best signing ever, and the rest of the NFL were dopes?

joshua.hermsmeyer: Cam’s QBR yesterday was 3.5, the third-worst performance by a QB this season and the second-straight game that he’s struggled since he returned after contracting the coronavirus. I really wonder if something physical is wrong. I know he hurt his hand, so maybe that’s it.

neil: I also saw some speculation about his shoulder, which is another injury that goes back a long time for him, off and on.

It doesn’t help that the Pats’ receiving problems seem to be as bad as ever. Julian Edelman had one catch (on three targets) for 13 yards.

joshua.hermsmeyer: Yikes.

neil: And he’s the only Patriot averaging over 40 yards per game receiving.

Salfino: I think we can legit wonder if Cam hasn’t fully recovered from COVID-19, but remember, Cam has been a HORRENDOUS passer since 2016.

neil: Thing is, he really only needed to be better than Brady passing while also bringing that rushing dimension. But he’s been much worse than Brady was.

sara.ziegler: And, of course, the Patriots have big problems on the other side of the ball, too.

Salfino: If only there were some college receivers the year the Patriots drafted N’Keal Harry in the first round.

sara.ziegler: I think everyone is waiting for Bill Belichick to come up with some magic solution to all of this, but that really doesn’t seem possible this year.

Salfino: I agree, the Patriots are toast.

joshua.hermsmeyer: If Cam gets healthy I think they can turn it around — assuming health is the issue here.

neil: Back-to-back home losses. When was the last time that happened to the Pats?

(I looked it up, and the last time that happened in the regular season was in Weeks 9 and 10 of the 2006 season.)1

Salfino: There are now about 10 things like this about them:

joshua.hermsmeyer: To Sara’s point, defense has been an issue for the Pats this year as well. After being perhaps the best defensive back in the league last season, Stephon Gilmore is the 50th ranked CB this season by PFF, and the Pats are 29th in net yards allowed per pass attempt.

Salfino: Man, the year-to-year variance for “shutdown CBs” is so high. I think the stats we use are bad, or it’s just too hard to suss out the best CBs. Like defense in baseball.

sara.ziegler: One other game to talk about quickly: In the battle of the unbeatens, Pittsburgh held on to beat Tennessee on Sunday. What did you all make of that game? None of you was all that high on the Steelers going into it…

Salfino: I still think Ben Roethlisberger is shot. It looked like he was going to make me eat my words in the first half, and then he was bad. The Titans were dancing with a damaged kicker and getting away with it, but they finally had to pay the piper.

joshua.hermsmeyer: I felt like Tennessee lost more than the Steelers won. Ryan Tannehill outplayed Ben slightly, but neither team looked particularly sharp.

neil: We knew the Steelers’ run defense was formidable — and they made Derrick Henry look mortal.

joshua.hermsmeyer: At least fantasy players were happy with that sweet A.J. Brown TD.

Salfino: Love the Pittsburgh defense. But the Titans helped them by throwing more passes to Corey Davis than Brown, even though Brown had five times as many yards.

neil: Oooof. Corey Davis: 3.5 yards per attempt on his targets.

Brown: 19.1

Salfino: That’s the ballgame.

sara.ziegler: It was a strange game. And now the Steelers have a 10 percent chance to win the Super Bowl, tied for third with the Ravens, in our model.

Salfino: I’m not loving any team in football, I have to say. Is it just me?

neil: The Chiefs certainly seem like a more flawed favorite than last year.

Salfino: The Bucs are probably the best team. God help us all if Tom Brady wins again.

neil: Maybe it was Brady and not Belichick all along!

Salfino: Spoiler alert!

sara.ziegler: LOL

Salfino: What is the deal with Antonio Brown? How can that help the program? Isn’t the downside too great?

Morality aside.

neil: He’s “matured,” haven’t you heard, Mike?

joshua.hermsmeyer: I don’t hate adding receiver depth. But I hate everything else about that move.

neil: Brady is so vindictive that he made them sign Brown just so the Pats wouldn’t.

(Not true. LOL)

Salfino: Antonio is being coached up by Banana Hands, too.

joshua.hermsmeyer: Breaking news: Odell Beckham Jr. is out for the season.

sara.ziegler: Oh, man.

Salfino: It’s a shame that his career, which was trending down, may now be over at such a young age.

joshua.hermsmeyer: He got injured trying to make the tackle after a Mayfield interception. Double-whammy play. Baker has been taking fire in Cleveland recently and was benched last week. I’m sure this won’t help things.

Salfino: Baker was 0-for-5 on his first five throws, including that pick, and then he went 22-of-23 with five TDs. He is cutting 1,000 commercials this week.

sara.ziegler: LOL, Mike.

Before we wrap things up, I did want to talk about another story that came out on Sunday. ESPN’s Adam Schefter reported that Ryquell Armstead, a running back for the Jacksonville Jaguars, won’t play this season because of complications from COVID-19. According to Schefter, Armstead has been hospitalized twice and has faced “significant respiratory issues.”

This sounds like the most serious case faced by any active athlete, and certainly within the NFL. Positive tests across leagues have tended to be asymptomatic, and though some prominent players have had symptoms — Ezekiel Elliot and Von Miller, for example — those players recovered and returned to football.

Armstead is very young — he turns 24 on Friday — and in exceptional shape. He was expected to compete for the starting RB role this year. His illness is a reminder that, though sports have brought us a measure of normalcy, we are still living in a terrifying pandemic.

neil: COVID-19 is a numbers game. And the NFL has a lot of numbers — with no bubble to really protect it.

Salfino: What’s happened to him is so scary. We’ve become desensitized to positive tests in sports with young and healthy athletes, but this is a grim reminder that the disease is so dangerous, no matter the age of the person it hits.

Check out our latest NFL predictions.