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Why the 2020 Cowboys should run less and pass more

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What worked and what didn’t work for the Cowboys last season and what it means for 2020.

NFL: New York Giants at Dallas Cowboys Jerome Miron-USA TODAY Sports

10 years ago, we took our first look at Expected Points Added (EPA) here on Blogging The Boys. At the time, EPA existed only in the form of Excel sheets passed around by email (I got mine from Brian Burke, then with AdvancedNFLStats), and manually calculating the EPA for every single play in a season was supremely time consuming.

We’ve come a long way since then, and while EPA is still not a mainstream stat in football, at least it’s readily available from sites like ProFootballReference.com, That’s laudable for a sport where a Super Bowl-winning coach can say things like “Stats are for losers. Final scores are for winners,” and goes unchallenged by beer-bellied sportswriters who still think it’s 1975.

Regardless, today we’re taking an EPA deep dive to understand what worked for the Cowboys offense in 2019 and what didn’t, and what it means for 2020.

What is EPA?

EPA is calculated by taking the expected point value (based on the league average results for that specific down, distance, and field position) before a play is run, and then subtracting it from the expected point value after a play is run.

The EPA for any given play is a value between -7 and +7. A positive value means the play contributed positively towards a score, a negative result means the play decreased the team’s odds of scoring.

EPA starts with the basic premise that not all yards are created equal. For example, a three-yard gain on 3rd-and-2 is much more valuable than a seven-yard gain on 3rd-and-8. Any measure of success must consider the down and distance situation, otherwise you’re firmly in the realm of fantasy football.

ESPN explained the concept in a little more detail when they started using EPA back in 2012:

To make the concept more tangible, here are some examples:

• From your own 20-yard line, an 8-yard gain on third-and-10 is worth about minus-0.2 EPA because you don’t get a first down; the same 8 yards on third-and-7 is worth 1.4 EPA for converting a long third down and keeping the drive alive. EPA knows that not all yards are created equal.

• A turnover on first-and-10 at midfield that is taken back to your own 20 is worth minus-5.5 EPA; a Hail Mary interception at the end of the half from midfield is not nearly as penalizing. EPA knows that all turnovers aren’t created equal, as well.

• A 60-yard pass play down to the 1-yard line on third-and-10 is worth 5.7 EPA because it puts you right on the doorstep of scoring. The subsequent 1-yard rushing TD on first-and-goal is worth much less, even though that’s the play that actually gets you the six points. Think about which play is more valuable to the offense (not in terms of fantasy football).

EPA is not “Success Rate”

“Success rate” (gaining 40% of the necessary yardage on first down, 60% on second down and 100% on third and fourth downs) is a term that is being used with increasing frequency by NFL observers and probably even some teams.

But underlying success rate is the fallacy of a “manageable third down”, which is something Cowboys fans still traumatized by the Garrett era should be especially wary of.

This is not a question of opinion, but a question of hard, historical data (even if many people are increasingly confusing these two things these days). The data clearly shows that outside of 3rd-and-1 there are no manageable third downs.

So, if your game plan is predicated on getting into manageable third down situations, you’re banking on converting some of the most difficult game situations to convert - again and again and again.

Using success rate leads teams to focus on maximizing success rather than maximizing the likelihood of scoring - which EPA focuses on.

For example, on 2nd-and-short, EPA suggests teams should probably be throwing down the field. But in many cases they do not, preferring instead to run the ball and thereby improving their success rate (and thereby setting themselves up for the dreaded “manageable third down”) and not necessarily their likelihood of scoring.

Using EPA (courtesy of Pro-Football-Reference.com), I can tell you exactly what each play in 2019 was worth.

  • The highest value non-TD pass? Michael Gallup’s 61-yard reception against the Giants in Week 1. EPA: 5.10
  • The most costly turnover? Deep pass to Amari Cooper against Green Bay intercepted by Jaire Alexander and returned for 37 yards. -5.51
  • Highest value defensive play? In Week 8, the Giants’ Daniel Jones was sacked by Dorance Armstrong and fumbled the ball. Jourdan Lewis recovered the ball and returned it for a touchdown. EPV: 10.97

2019 EPA

BTB-member VAfan recently posted a very nice breakdown of the 2019 EPA season totals for the Cowboys. Here are some of his findings:

The Dallas offense was actually 2nd in EPA, with 214.77 EPA, behind the Ravens at 249.1.

The Cowboys defense ranked 13th in the NFL with -36.81 EPA.

There is no table ranking teams by Special Teams EPA, but the Cowboys were woeful by any measure, with -65.31 EPA on special teams.

Overall, the offense had a positive EPA in 14 of 16 games. The defense was positive in 7 of 16 games. Special teams was positive in 2 of 16 games.

Building off those numbers, today we’re going to look at the 2019 EPA for the Cowboys’ offensive personnel, but instead of looking at the cumulative numbers, we’ll work with EPA per play, and we’ll start with the ground game.

Dallas Cowboys running game EPA

Including turnovers on running plays, the total EPA for the Cowboys’ ground game adds up to 53.2 on 438 runs (excluding 10 QB kneels). That’s an EPA of 0.12 per run, which means the Cowboys get a positive contribution from the running game, but just barely. Here’s how that breaks down by player:

Player Runs Total EPA EPA/play
Tavon Austin 6 3.8 0.6
Dak Prescott 42 22.3 0.5
Ezekiel Elliott 301 22.2 0.1
Tony Pollard 86 5.6 0.1
Randall Cobb 3 -0.7 -0.2
Total 438 53.2 0.1

For the ground game, the data here suggests that Dak Prescott should run more; per EPA, he’s averaging half a point per run. That’s pretty impressive. Consider also that Lamar Jackson averaged 0.56 EPA/play, and Prescott’s 0.53 EPA/play is only marginally lower. Of course, Jackson ran a lot more, but the Cowboys may want to think about adding more plays designed for a QB run, and ESPN’s Bill Barnwell agrees:

Prescott has been an incredibly valuable runner over the past four seasons. He’s second over that time frame among quarterbacks in rushing expected points added (EPA), fifth in rushing yards and third in first downs, and has a league-leading 21 rushing touchdowns. By Football Outsiders’ yards above replacement metric (DYAR), he has produced a league-best 404 DYAR over the past four seasons.

What’s true for Prescott is also true for Tavon Austin: the Cowboys will improve their likelihood of scoring if they find a gimmick player to give touches to this year. Of course, just having anybody run those gimmick plays may not be the solution, as Randall Cobb’s numbers suggest.

But what’s up with Ezekiel Elliott and Tony Pollard? At first glance it doesn’t look like either players is contributing much in terms of points added. But the Cowboys ranked fifth in total rushing yards last year, so how does that compute?

The simple answer is that EPA is about points, not yards.

A better answer is that in terms of EPA, the average combined value of runs for most of the field is close to zero. Here’s why: a first-down play needs at least four yards to be break-even in terms of EPV, and in the NFL last year, 55% of runs (3,691/6,753) on 1st-and-10 gained less than four yards.

So if you’re in a situation where half your runs have a negative EPA and the other half has a positive EPA, your total running EPA should be at or around the zero mark. So the Cowboys aren’t doing that badly with a 0.1 overall EPA/play.

But there’s another reason for Elliott’s low EPA, and that has to do with how the Cowboys used him.

Ezekiel Elliott Runs Total EPA EPA/play
1st-and-10 175 7.1 0.0
2nd/3rd and less than 5 57 17.8 0.3
2nd/3rd and long 50 -0.11 -0.0

The Cowboys arguably ran too often on 1st-and-10. Elliott rushed 175 times on 1st-and-10 for a total EPA of 7.1, Tony Pollard added 44 more runs on 1st-and-10 for an EPA of 1.9. In total the Cowboys rushed 233 times on 1st-and-10 for a 12.1 EPA, or an EPA/play of almost zero.

All of this of course is born out of the outdated notion of “establishing the run” and its nefarious cousin “run to set up the pass.”

In a world before EPA, it was a widely held belief that there were some important benefits provided by the run game: helping out the defense by controlling the ball, tiring out defenses with ground-and-pound, and, of course, the holy grail of run-first truthers: setting up the pass.

All of which has been thoroughly debunked by the statistical community, but facts and belief systems never mix well, and so the run-first discussion continues.

Be that as it may, like many other teams, Garrett’s 2019 Cowboys were quite happy to commit to low-EPA over high-EPA plays. Perhaps Mike McCarthy’s newfound fondness for analytics will change that, we’ll see.

This next table is the same table we used to look at Elliott’s EPA by game situation, only this time we’re looking at the total passing game:

Passing game Pass Attempts Total EPA EPA/play
1st-and-10 207 42.2 0.2
2nd/3rd and less than 5 90 15.45 0.2
2nd/3rd and long 291 117.4 0.4

From an EPA point of view, the passing game delivers superior results on 1st-and-10 and significantly superior results on 2nd and 3rd-and-long. And that passing game includes all the sacks, interceptions, and incompletions the Cowboys had last year. Where the Cowboys ground game comes out ahead is on second and third down with less than five yards to go.

So if you need chunk yardage, you go with the passing game, if you just need a handful of yards, it’s okay to hand the ball to your backs. That, in a nutshell, is what today’s analytics are telling the NFL, but it’s not entirely clear who is listening.

Dallas Cowboys passing game EPA

Same exercise for the top eight receivers from last season:

Receiver Targets Total EPA EPA/play
Amari Cooper 119 64.2 0.54
Michael Gallup 113 57.1 0.51
Randall Cobb 83 41.2 0.50
Blake Jarwin 41 14.4 0.35
Jason Witten 84 24.7 0.29
Tavon Austin 24 6.2 0.26
Ezekiel Elliott 71 11.2 0.16
Tony Pollard 20 -2.4 -0.12
Total 620 168.0 0.27

The data here is pretty straightforward. The Cowboys have three tiers of receivers.

Tier 1: The top three receivers all average around 0.5 EPA per target. These are very solid numbers, and the Cowboys will have to hope CeeDee Lamb can step in and seamlessly replace Randall Cobb, which is no small task from an EPA point of view: If we were to exclude interceptions from the receiver totals, Cobb (0.66 EPA/Play) would lead Cooper (0.63) and Gallup (0.60) - if only marginally.

Tier 2: The two tight ends make up this second group. Nowhere as effective as the wideouts, but still a better option than the running backs. Based on these numbers, Jason Witten was probably over-targeted in his final year in Dallas, but Blake Jarwin’s numbers should give hope for 2020.

Tier 3: The running backs, to nobody’s surprise, are not a particularly efficient part of the passing game. Of course, it doesn’t help that Pollard and Elliot frequently had to help out as Checkdown Charlie on broken plays.

Apart from the hyper-obvious “pass more, run less,” the data here suggests a few things the Cowboys might want to look at heading into the 2020 season:

  • 11 personnel: If every target to a wide receiver delivers 0.5 EPA/play, we should see even more 11 personnel (1 RB, 1 TE, 3 WR) on the field. It is already the Cowboys’ default offensive formation, and its use has steadily increased recently before dipping slightly last year. In 2015, the Cowboys were in 11 personnel on 51% of their plays. That number increased to 61% in 2016 and 2017 before jumping to 68% in 2018 and then slipping a little to 67% last year.
  • Play-action them to death: Everybody expects the Cowboys to run on 1st-and-10. So instead, why not run play-action, a read-option, or an RPO play on every first down? The opposing defense will key on Elliott, opening up room for quick completions over the middle or - wait for it - QB runs in the opposite direction.
  • Use a tackle to block: If you need a TE to help you block, use a tackle instead. If you need a TE to run a pass route, use a WR instead (Hint: you have enough of those).
  • Don’t throw to your running backs. They may be “dangerous in space” but that space is never behind the line of scrimmage.

And, oh yeah, pass more, run less.