Establishing the run and controlling the clock are central tenets among coaching staffs throughout the NFL. A couple of weeks ago, we looked at how establishing the run and being successful with it really doesn’t affect wins and losses. Now we’re going to look at time of possession and why worrying about it is a total waste of time.
Below are two scatter plots showing the same information from the last three seasons. One is winning as a function of time of possession, and the other is the inverse.
So the question becomes this - does time of possession affect winning, or does winning affect time of possession? There are two paths to follow, and both lead to the same answer.
The first and most brief path is one of simple logic. Possessing the ball for an extended amount of time does not affect the structure of the game. Coaches may say things like “We have to keep the other team’s offense off the field,” but the rules don’t allow that. Unless a team is able to repeatedly recover their own onside kicks, both teams in a given game of football will get equal opportunity to possess the ball. Total number of possessions may be reduced, but all that accomplishes is introducing more luck and variance into the result i.e. turnovers and fluke plays have a greater effect on the final outcome.
In short, the goal of reducing your opponent’s possessions is only accomplished via reducing your own possessions. There’s no advantage gained there.
The other common defense of winning the time of possession battle is that it keeps your defense off the field, meaning they’ll be fresh when they take the field. With that comes the assumption that a fresh defense is a better defense. Here’s the relationship between time of possession and yards per play allowed on defense.
That’s about as horizontal line as you’re going to find.
If a team’s defense is good, it’s good. There are no indications that good defenses are aided by their offense chewing up clock, which makes sense. Defenses can rest on the sideline as long as their offense is on the field. The amount of game time that ticks off the clock does nothing to affect the amount of real time the defense spends resting.
So the answer to the initial question posed above is becoming clearer - winning the time of possession battle does not seem to be a means to an end. Rather, better time of possession statistics are a result of teams outperforming their opposition.
As proof of this, look at the below scatter plots. The first is the relationship between the frequency of run plays and time of possession. This is an illustration of how successful teams are at controlling time of possession by running the ball.
The second is the relationship between net Drive Success Rate (via Football Outsiders- The percentage of offensive series that result in a first down or touchdown) and time of possession. This is an illustration of how successful teams are at controlling time of possession by simply being better than their opponents at getting first downs.
It’s cut and dry. Time of possession is a result, not a process. And the means to get those results tie back in with the previous article. Below is how net yards per carry and net passer rating affect drive success rate.
That’s another W for the passing game.
The moral of the story is that NFL coaches need to stop worrying about controlling the clock by pounding the rock. Build your team around the passing game, pick up first downs, and the rest will take care of itself.