The Power Sweep

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TPS Advanced Stats: Total Pressures

No single stat leads to more misplaced analysis than the sack.

Dating back to when Deacon Jones coined the term, the act of tackling a quarterback as he attempts to pass has come to define pass rushers. Players earn Pro Bowls, All Pro nominations, and millions of dollars based on their ability to sack the quarterback.

Never mind that the stat doesn’t indicate how a sack was collected or which players got after a quarterback without managing to get to him before he released the ball. It’s sacks and only sacks forever.

But it doesn’t have to be this way.

Something more than sacks

Quite a few NFL media outlets have begun to track players’ abilities to get to the quarterback in ways that go beyond just a sack. Pro Football Focus is probably the most notable, tracking Pass Rush Percentage as part of their fleet of premium metrics.

On a more simple level, former Packers beat writer Bob McGinn also tracked more than sacks, rating players on their ability to collect what he called “pressures.” Pressures were a combination of the times a player sacked, knocked down, or hurried a quarterback into an early throw. This simple three part stat goes beyond the box score and gives a bit of a more in-depth look into who’s producing on defense.

Following McGinn’s departure from the Milwaukee Journal Sentinel, we figured someone should take up the mantle of tracking the stat he’s tabulated for decades. As a result, we’re pleased to introduce our second advanced metric: Total Pressures.

In equation form, here’s how we’ll be running our calculations:

Total Pressures = Sacks + Knockdowns + Hurries

What does it mean and why do we like it?

It’s pretty obvious that defensive players can do more to affect an opposing team’s passing game than just sack the quarterback. This stat should show us who is (and who isn’t) making life miserable for opposing quarterbacks.

To define our terms, let’s look at some examples of the plays we’ll be tracking.

We all know what a sack looks like, but just for the sake of consistency, here’s Nick Perry sacking Sam Bradford.

via GIPHY

As a point of further clarification, we will attempt to follow NFL guidelines when it comes to half sacks. Though there is a case to be made that sacks shouldn’t be split, we’re content to follow the league’s protocol on this and we’ll refer to their numbers on sacks when relevant.

Knockdowns, too, are pretty straightforward. When a player knocks down a quarterback as or even after he attempts a pass, it can affect the throw. Here is Clay Matthews knocking down Sam Bradford.

via GIPHY

Hurries are a little more nebulous. It will depend a lot on the eye of the beholder what, exactly, will qualify as a hurry, but we’re defining it as a player forcing the quarterback to throw before he appears ready. This could be a ball thrown out of bounds, to the feet of a receiver, or even a completion under duress.

Here, Clay Matthews forces a hurried throw from Sam Bradford.

via GIPHY

This play is instructive because although Matthews did his job, the Vikings still succeed on the play. We credit Matthews with a hurry, but coverage that’s slow to react means the play still ends up as a success for Minnesota.

But even if Matthews didn’t manage to completely change the outcome of this play, he did force Bradford to throw to a non-primary option. Running a two minute drill late in the first half, the Vikings surely didn’t want to settle for dumping the ball out to a safety valve option, and Matthews forced them into a situation that could have resulted in more time bleeding from the clock or Minnesota burning a timeout.

In a nutshell, this is exactly why we need stats like Total Pressures. Sacks only account for plays where the defense unequivocally beats the offense, but that’s just a small percentage of what happens during a game. In reality, quality players affect the game play in and play out, and total pressures attempts to measure that.

What does it tell us about the Packers?

For now, not a lot. We only have McGinn’s final totals for this stat for last season, and we don’t get to see the full breakdown of how individual players did on sacks versus knockdowns and hurries.

He does give us a tantalizing glimpse, though. In his year end column, McGinn says the Packers had 60 total knockdowns, led by Datone Jones with 14. Mike Daniels led the team in hurries with 20.5

Here’s McGinn’s top five list of Total Pressures for 2016

  • Nick Perry - 36
  • Julius Peppers - 32.5
  • Mike Daniels - 31.5
  • Datone Jones - 31.5
  • Clay Matthews - 28.5

Incomplete though the current data may be, our Total Pressures stat will only get better with time. We’ll be able to track player performance year by year and game by game, getting a better look into who’s really producing for the Packers.