When a quarterback is sacked, the box score charges the team, and most fans blame the offensive line. Our quarterback rankings count sacks against the quarterback. Here is why.
A sack has three parts
Every sack combines the pass rush, the protection and the quarterback's decision. A defensive end who beats a tackle in two seconds deserves the credit. But many sacks take three, four or five seconds, and by then the quarterback has made choices: hold the ball and wait for a route to open, throw it away, check it down to a back, or step up and run.
Sack rate follows quarterbacks
Analysts who have looked at quarterbacks who changed teams have found that their sack rates tend to come with them more than they stay with the old offensive line. Quarterbacks who process quickly and get rid of the ball keep low sack rates behind different lines; quarterbacks who extend plays looking for something big take more sacks wherever they go. That is a pattern, not a law: a bad line still produces sacks.
Sacks are expensive
A sack on 2nd and 8 turns into 3rd and 15, where an average offense converts far less often. In expected points, a typical sack costs more than an incompletion, and some cost as much as an interception. Ignoring sacks, as passer rating does, gives a quarterback who takes them a free pass.
How we count them
- EPA per dropback counts sacks as dropbacks, with their full expected-points cost.
- Sack % is sacks divided by attempts plus sacks. Lower is better.
- ANY/A (adjusted net yards per attempt) subtracts sack yards and counts each sack as an attempt.
- Negative-play rate counts sacks, interceptions and completions that lost yards per dropback.
The other side
Some quarterbacks take sacks because they refuse to throw into danger, and some of their long scrambles come from the same patience. That is why we show sacks next to scrambles, rushing EPA and interception rate, never by themselves. A quarterback with a high sack rate and a very low interception rate may be making a reasonable trade. The team pages show sacks allowed for the whole offense, and the Top Passing Teams cards break each team's expected points into passes, sacks, scrambles and designed runs so you can see where the points go.