In a recent article, I detailed a way in which analytics — in particular, taking advantage of tracking data — can help teams find opponents’ tendencies. Let’s do just that — honing in on the Kansas City Chiefs’ upcoming playoff matchup with the Houston Texans.
While not as predictive as offensive Expected Points Added (EPA) per play, defensive EPA is significantly correlated with future defensive performance; specifically, defensive EPA per play is about half as predictive as the offensive version.
Overall, the Texans gave up 0.10 EPA per play this season — good for the 27th best defense in the league. Against the pass, the number was 0.19 (25th). They fared slightly better against the run, limiting opponents to -0.05 EPA per play (20th).
This is consistent with Football Outsider’s DVOA metric, which adjusts defensive performance by the strength of the offenses they faced. In their calculation, the Texans are ranked as 2019’s 26th-best defense.
This bodes well for the Chiefs — a team with a top offense that finds its strength moving the ball through the air. Are there any specific vulnerabilities the Chiefs can look to exploit?
This chart plots defensive Completion Percentage Over Expectation (CPOE) — that is, how well the Texans do compared to an average NFL defense — in different parts of the field. The bluest areas are the ones where they do best; the most-orange areas show where they are weakest.
Despite ranking as one of the worst pass defenses in the league, the Texans actually allow a smaller percentage of deep passes (greater than 30 yards) to be completed. But we also that they’re vulnerable in the short to intermediate middle of the field.
Here’s the CPOE data for the Chiefs offense compared to an average NFL offense — but this time, the colors are reversed, showing Patrick Mahomes completes a very high percentage of his passes to the deep middle of the field.
So given this comparison, the Chiefs likely won’t — and shouldn’t — change where they choose to attack the Texans defense. They’ve been one of the best teams in the league at attacking the deep middle — and thus shouldn’t be deterred.
On offense, the Texans added 0.10 EPA per play — good for sixth in the league. They have a very well-balanced offense, too. Their passing attack is ninth-best with 0.16 EPA per play, while they’re sixth-best at rushing with 0.00 EPA per play. (Remember: on average, passing is more efficient than running).
Where does Deshaun Watson like to go with the ball?
This chart shows how often particular areas are targeted — the greenest areas are targeted the least, while the darkest-orange see the most targets.
Watson largely mirrors the NFL average — aside from slightly favoring the left side in the short-to-intermediate range. How successful has his approach been?
Here we see Watson’s CPOE in different parts of the field — and it’s pretty good.
While Watson doesn’t have the extreme values (more than 30% over expectation) that Mahomes shows in the deep middle, he has been fairly accurate all over the field — completing more passes than the league average.
Fortunately for the Chiefs, their pass defense has been rock solid this year. Whether that trend can continue without rookie safety Juan Thornhill will likely be one of the deciding factors in this game.
Unlike the Chiefs, the Texans have been quite aggressive on fourth down this season.
Ben Baldwin looked at situations where the games aren’t out of hand (that is, when teams have no choice) and calculated how often teams go for it on fourth down — and whether the odds are in their favor when they do. (Hint: the odds favor going for it).
Final 4th down aggressiveness in 2019 pic.twitter.com/TIUw1NVboj— new-age analytical (@benbbaldwin) January 2, 2020
The Texans rank fourth, going for it almost 50% of the time — while the Chiefs are in the lower half of the league, going for it only around 30% of the time.
As previously mentioned, relative to the rest of the league, the Texans have well-balanced between passing and rushing. This is reflected in their play-calling as well. On early downs, the Texans pass the ball just under 55% of the time — compared to the Chiefs 67%. When you’re used to watching the Chiefs offense, that looks run-heavy — but it’s actually quite in line with the league average.
So what does it all mean?
The Chiefs top-ranked passing offense will be going against a Texans defense that is one of the worst in the league. While the Texans don’t differ much from league-average trends in their offensive approach, they have been formidable — but so as the Chiefs passing defense.
That leaves us with a strength against a weakness — and a strength against a strength. And at the end of the day, it is offensive stats that drive NFL wins. (Remember: offensive EPA per play is more predictive than defensive EPA per play).
It’s a playoff game and the Texans aren’t a bad team — but on this one, the metrics certainly favor the Chiefs.