NFL News & Analysis

Premium Content Sign Up

PFF Data Study: How luck, and not skill, can help pass-rushers to a career year

Just last week, we revisited the idea of the “sack artist” and found that they don’t actually exist. Instead, our research led us to the conclusion that the rate at which a pass-rusher turns pressures into sacks is not stable from season to season, even after accounting for situational factors.

That being said, nothing is more valuable to a pass-rusher than sacking the opposing quarterback. So, hypothetically, if a pass-rusher was to face the same schedule of offensive linemen as any other pass-rusher, the value of a pass-rusher in a given season depends on two things:

1. His true ability, which controls his pass-rush win rate and (to a great extent) his pressure rate.

2. His luck, which controls the number of pressures he can turn into sacks.

The natural question is, which of these two things matters more? If player A is more skilled than player B, but player B is luckier (with the same magnitude than he is less skilled), who will have provided more value at the end of the season?

[Editor’s Note: PFF’s Player Grades, WAR metric, etc.  are powered by AWS machine learning capabilities.]

The first question is what we mean by “the same magnitude.” To talk about this, we have to bring these two things on the same scale — we have to understand their distributions.

To bring luck and skill on the same scale, we will use percentiles of these distributions, i.e., we compare an edge rusher who is better than 70% of all edge rushers to an edge rusher who has more luck than 70% of all edge rushers in a given season.

We will simulate a pass-rusher’s season with different levels of true ability and luck. Any conclusions driven from this will only make sense if these two things are entirely independent, and that’s indeed the case: Players who generate more pressures are neither worse nor better at turning these into sacks than worse pass-rushers who generate less pressure. The R-squared values are below 0.005 for both edge rushers and interior rushers.

In other words, every NFL pass-rusher is at the mercy of the circumstances that allow them to turn their pressure into sacks.

Running the simulations

As you could have already guessed, we run separate simulations for edge rushers and interior pass-rushers. In each simulation, we simulate the downs and distances the opposing offense will face and simulate pressures and sacks based on these situational factors. The total numbers of pressures and sacks determine the shift in expected points added for the offense based on the numbers we already wrote about.

Subscribe to PFF Edge to continue reading

Already have a subscription? Sign In

Tackle Lifes financial Challenges. Western Southern Financial Group.

NFL Featured Tools

  • PFF's Best Bets Tool reveals the bets PFF's data and algorithms give the biggest edge to within spread, total, player prop, and moneyline markets.

    Available with

  • PFF predictions and real time spread, moneyline and over/under lines for each NFL game.

    Available with

  • PFF's Player Props Tool reveals betting opportunities within player prop markets.

    Available with

  • Power Rankings are PFF’s NFL power ratings based on weekly player grades in each facet of play. These power rankings are adjusted based on coach, quarterback and the market each season.

    Available with

  • PFF's exclusive metrics provide matchup previews, position rankings, grades, and snap counts.

    Available with

  • Our exclusive database, featuring the most in-depth collection of NFL player performance data.

    Available with

Pro Subscriptions

Unlock NFL Player Grades, Fantasy & NFL Draft

$9.99 / mo
$39.99 / yr

Unlock Premium Stats, PFF Greenline & DFS

$34.99 / mo
$199.99 / yr