It’s been pretty obvious to anyone who has watched the Detroit Lions over the first nine weeks of the 2021 NFL season that the passing offense has not been good. Thanks to the data miners at rbsdm stats, there is graphic representation of just how inefficient the Lions passing offense–specifically quarterback Jared Goff–has been over the first half of the season.
In the graph below, which sorts quarterback efficiency for QBs with at least 200 plays, Goff is in a quadrant almost all to himself at the very bottom.
The graph measures expected points added per play against completion percentage above expectation per play. Garbage time, defined as a win probability outside the window of 10 to 90 percent, is filtered out. The methodology explaining EPA:
This is done by calculating “Expected Points” for every down. Through the use of historical data, “Expected Points” are calculated for any given play based on down, distance, and field position. Then, expected points is contrasted against the actual result of each play in order to determine the expected points added on the play.
And the completion percentage above expectation, which does indeed factor in the defense, the game and throw situation and the receivers in play,
This stat measures a QB’s performance on any given throw relative to the difficulty of that throw. Expected completion percentage is determined by air yards, target distance from closest defender and sideline, QB distance from closest pass rusher, speed at time of the release (throwing on the run), and time to throw the ball.
Goff is near the average in completion percentage versus expectation, but the EPA figure is three full lines of demarcation lower than the next-worst, Carolina’s Sam Darnold, who has been benched on multiple occasions thus far.
One big reason for Goff’s lowly status is his air yards per attempt. Goff currently sits at 5.7. That’s almost a full yard below Kirk Cousins of the Vikings, who is the next in line above Goff.
