Can Steelers Carry Turnover Success Into 2020?
Turnovers are among one of the most exciting events to take place during a football game. Whether it be a Minkah Fitzpatrick pick-six or T.J. Watt strip-sack, terrible towels are sure to be fired up and waved when an event like a fumble or interception occurs.
In 2019, Pittsburgh delivered in the turnover department, leading the league with 38 turnovers. Averaging a little over two turnovers per game, there's no doubting Pittsburgh's defense was a heavy reason of any success the team sniffed in 2019. At a rate of two turnovers generated per game with the offense not turning the ball over (or a +2 turnover difference), a Harvard sports analytical study found that teams with a +2 turnover differential have an 83.9% chance of winning.
That's a huge but random advantage, and it doesn't necessarily guarantee a victory. However, generating turnovers is just one of the few metrics used to measure a great defense, and the 2019 Steelers excelled in that department.
So with a healthy Ben Roethlisberger returning to an offense with new weapons and healthy players to start the season, it's logical to believe if Pittsburgh's defense can prove their up to the task again in 2020, there's a playoff game in the Steelers future.
The only problem? Turnovers are (from a predictability standpoint) completely random. That same Harvard study found the following conclusion after a twelve year data study:
"So after a few hundred words of statistics, we arrive at a whopping conclusion that just over half of seasonal turnover differential is due to luck. That’s huge, especially when you consider that (from earlier) seasonal turnover differential explains over 40% of seasonal winning percentage... Ultimately in a 16-game season, there’s just a whole lot of luck involved with winning football games and for all that commentators will talk about defensive schemes forcing turnovers this season, it’s just as important to be lucky as to be good."
What should we expect out of the Steelers defense from a statistical standpoint? I tried my hand at trying to find what data could help Pittsburgh carry their turnover success into 2020.
As a base model, I tracked the last five years of defenses that led the league in turnovers and tried to find any carrying statistics, if any, that helped continue the amount of turnovers following their league-leading season:
| Team | Turnovers (League-Leading Year) | Turnovers (Year After Leading League) | Turnover Difference | Percentage Drop |
|---|---|---|---|---|
Houston | 34 | 25 | -9 | 27% |
Carolina | 39 | 27 | -12 | 31% |
Kansas City | 33 | 26 | -7 | 22% |
Baltimore | 34 | 17 | -17 | 50% |
Chicago | 36 | 19 | -17 | 48% |
As it turns out, it's extremely hard for a team to go back-to-back seasons in leading the league in turnovers. It's also difficult for defenses to replicate the same rate of turnovers, with the last two league-leaders in that category (Chicago and Baltimore) seeing substantial drops (17 turnovers each) the following season.
On average, the last five years produced an average of a 35% drop in turnover production, with 12.4 as the mean number.
When applied to Pittsburgh's 2019 total of 38 turnovers, our statistical trend has the Steelers tallying 25 turnovers in 2020. This would have tied for seventh-best in the NFL in 2019.
I identified three main statistical categories that could potentially tie success on a year to year basis in terms of turnovers:
Sacks
It makes sense, right? Nearly one in every five sacks in the NFL result in a fumble and thus creates a chance for a turnover. Sacks also loosely indicate that a defense is pressuring a quarterback consistently, although pressure rates and sacks are not tied to each other. A pressured quarterback is bound to make mistakes sooner or later.
| Team | Sacks in Leading Year | Sacks in Following Year |
|---|---|---|
Houston | 38 | 45 |
Carolina | 44 | 47 |
Kansas City | 28 | 31 |
Baltimore | 41 | 43 |
Chicago | 50 | 32 |
With 4/5 teams actually increasing their sack totals in the year after their turnovers dropped, it appears as if sacks are as random as turnovers themselves, and thus I cannot draw a correlation between the two. However, it is notable that 3/5 teams also stayed within a 3 sack distance of the prior year.
Rush Defense
If sacks won't do it, maybe rush defense will. The ability to stop the run and force an offense to become one dimensional is a highly coveted ability by defensive coordinators. More passes= more opportunities to intercept the ball.
| Teams | Rush Defense Rank in Leading Year | Rank After Leading Year |
|---|---|---|
Houston | 10 | 10 |
Carolina | 4 | 6 |
Kansas City | 26 | 25 |
Baltimore | 15 | 4 |
Chicago | 1 | 9 |
3/5 teams actually stayed even or improved their rush defense after leading the league in turnovers, with the other two teams (Carolina and Chicago) dropping just an average of five spots in the total standings.
It's interesting to see Kansas City stayed near the bottom of the league in rush defense for both seasons in our study ranking 26th and 25th respectively. The rest of the teams show that your defense must at least be average in stopping the run to have a chance in replicating turnovers.
However, there's nothing here that suggests stopping the run is indicative of generating turnovers, and thus cannot be used in support.
Pass Defense
Pass defense is ironically my "Hail Mary" attempt in finding any major statistical correlation for continuing turnover success. With sacks and stopping the run failing us, our last chance rests within the secondary.
| Teams | Pass Defense Rank When Leading in Turnovers | Pass Defense Rank Year After Leading League in Turnovers |
|---|---|---|
Houston | 21 | 3 |
Carolina | 11 | 29 |
Kansas City | 18 | 29 |
Baltimore | 10 | 5 |
Chicago | 7 | 9 |
Yeah, this table is all over the place. Teams such as Baltimore and Chicago maintained top-ten status in both seasons, while we saw incredible drops from teams such as Carolina and Kansas City, both plummeting near the bottom of the rankings in the year after leading the league in turnovers.
Then you have Houston, who jumped from 21st to 3rd after generating the most turnovers in the league. It's safe to say this category was as random as any you could find, and thus I can't reasonably ping this with turnovers.
Working Back to Pittsburgh
What did we learn from our short statistical analysis? Turnovers have no true correlation, supporting the theory that they are a solid combination of luck and timing. Of course the nice people at Harvard could have (and did) suggest that from the start.
If we can't tie any statistical findings to turnovers, the next best thing is to evaluate Pittsburgh's individual chances in 2020.
Out of 38 turnovers in 2019, exactly 20 of those were a result of interceptions. The Steelers joined the Patriots as the only team in the league to have 20 or more takeaways through the air.
Below is a chart of the starting quarterbacks the Steelers are slated to face in 2020, and their interception percentage (interceptions thrown/passes attempted) from last season.
| Team | Quarterback | Interception Percentage |
|---|---|---|
Baltimore Ravens | Lamar Jackson | 1.5% |
Cincinnati Bengals | Joe Burrow | N/A |
Cleveland Browns | Baker Mayfield | 3.9% |
Buffalo Bills | Josh Allen | 2% |
Dallas Cowboys | Dak Prescott | 1.8% |
Denver Broncos | Drew Lock | 1.9% |
Houston Texans | Deshaun Watson | 2.4% |
Indianapolis Colts | Philip Rivers | 3.4% |
Jacksonville Jaguars | Gardner Minshew | 1.3% |
New York Giants | Daniel Jones | 2.6% |
Philadelphia Eagles | Carson Wentz | 1.7% |
Tennessee Titans | Ryan Tannehill | 2.1% |
Washington Redskins | Dwayne Haskins | 3.4% |
With a league average of 2.9% of pass attempts resulting in interceptions, the Steelers are slated to face just three quarterbacks (Mayfield, Rivers and Haskins) that meet the criteria. Dropping the criteria by half a percentage point to 2.4%, the only new additions to the unfortunately-generous club are Daniel Jones (2.6%) and Deshaun Watson (2.4%).
I was hesitant to apply a figure to Bengals rookie quarterback Joe Burrow, as there are a number of factors that could sway his figure. I decided to exclude him statistically until we have actual data from Burrow.
Statistically speaking, the Steelers will play five quarterbacks next season that are near the league average when it comes to throwing interceptions. With a solidified secondary that includes Joe Haden, Steven Nelson, Mike Hilton and Minkah Fitzpatrick, the team is almost sure to capitalize on errant passes in 2020.
The amount of passes they'll intercept remains a mystery, and with fumbles occurring on 1.67% of all plays, both are hard to predict on any basis.
Conclusion: Randomness Perseveres
After reading through a number of articles, data and various other outlets in search of a simple correlation to continue turnovers at a high level, the answer is clear: Turnovers are random, and cannot fairly be predicted.
Does this mean Pittsburgh won't generate a large amount of turnovers? That is not to say. The Steelers have an extremely talented defense. However, going into this study I knew replicating a high number of turnovers might be unrealistic, and the above data supports that line of thinking.
The turnovers will continue to come, but don't expect to see Minkah waving goodbye to his opponents as often as he did in 2019.
