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A Quarterback Rush Attempt is a Sack Avoided

This post isn’t specifically about Michael Vick, though it is certainly prompted by his return to prominence. One of the things that you must consider when evaluating a quarterback is the percentage of times he takes a sack. Most commentators and members of the main stream media put the blame for sacks on the offensive line. They can certainly have breakdowns that lead to specific sacks, but when we look at larger samples across an entire season, we find that sack rate belongs to a quarterback every bit as much as other measures that we generally ascribe to him, but which are also heavily influenced by teammate contribution and circumstance, such as yards per attempt and interception rate. 

Last year about this time, I looked at what quarterback rate stats stayed most consistent when a quarterback changed teams, and conversely, when a team changed quarterbacks mid-season. Sack rate rated among the most consistent when a quarterback switched teams, and among the least consistent when the team switched quarterbacks. This suggests that the quarterback himself, and how quickly he processes information and senses pressure, has a lot to do with the number of sacks he takes.

Which brings us to Michael Vick. If you are going to evaluate Vick’s effectiveness, you do have to account for the sacks that he takes. So far this year, Vick has been sacked 11 times for -71 yards, leading the league in both categories. That rate is roughly in line with his career averages, as in Atlanta, he was sacked roughly 9.8% of the time.  That equates to a Sack%+ score of 78 for his career, which means he is about 1.5 standard deviations worse than an average quarterback at taking sacks.

But is he really that bad at taking sacks?  We think of Vick as a running quarterback, and credit his runs to the rushing yard totals.  The vast majority of his runs when he is playing as the starting quarterback, though (as opposed to in a Wildcat formation) are coming out of passing plays.  It is true that by traditional sack rate (which is calculated as sacks divided by pass attempts + sacks), running quarterbacks usually take an above average number of sacks.  How much of that, though, is negated by the fact that a rush attempt for a running quarterback is usually a sack avoided?

Whereas a pocket passer who rarely goes past the line of scrimmage will throw the ball away, or will check it down to a back, the running quarterback will break the pocket and try to gain yards himself.    If we are going to penalize him for sacks taken when he fails to get back to the line of scrimmage, we must also credit him for sacks avoided when he gets past the line of scrimmage.  To try to assess the impact of failing to consider rushing plays as sacks avoided, I looked at all seasons where a quarterback rushed for 400 or more yards in a season since the merger, and looked at their sack rates.

As a group, their traditional sack rate was 8.2%, and that translates to a Sack%+ of 93 (Sack%+, like baseball statistics such as OPS+, normalizes to league average, where a score of 100 is average and 93 is below average).  If we include rush attempts for the quarterback in with pass attempts though, that rate drops to 6.9%, which is pretty much league average.  Now, not all rush attempts are sacks avoided (you also have kneels, sneaks, and designed draws) but the vast majority for a running quarterback are.  It appears, then, that a large part of the difference between running quarterback’s sack rates and others is the failure to consider a rush attempt as a sack avoided.

In Vick’s case, if we are going to praise his highlight runs, we must recognize the negative plays.  Conversely, though, we should not chide the negative without considering that the runs are also sacks avoided. [Image via Getty]

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