Chicago returns their entire secondary from last season, which is good news.
Off-season additions like Eddie Jackson and Prince Amukamara, coupled with breakout seasons from Kyle Fuller and Adrian Amos, helped construct a quality 2017 pass defense. The Bears were 7th in passing yards allowed, 15th in yards per attempt, and 5th in fewest touchdown passes given up.
But there is one area where improvement is desperately needed: interceptions. The Bears caught only 8 for the third year in a row in 2017. Only two NFL teams had fewer.
This has to change if the Bears want to become a good team. To understand why, let’s look at how important turnovers are to winning football games.
Turnovers & Winning Games
Over the last five years, there is a correlation of 0.50 between a team’s turnover differential and the number of wins for a given season. That means that roughly half of a team’s season outcome can be explained simply by looking at how many times their offense turned the ball over compared to how many times their defense took the ball away. Other studies have looked at this in greater detail and found the correlation to be somewhere between 40% and 65%.
I wanted to put this into a visual that’s a bit more concrete, so the table below shows how a team’s turnover differential corresponds to various season outcomes over the last 5 seasons (full data available here).
Teams that have a better turnover differential win more games and make the playoffs more often. It’s not a revolutionary idea, but I think it’s helpful to see some numbers.
Fumble Luck Doesn’t Last
So if the Bears want to improve, they need to improve their turnover differential. They actually weren’t awful last year (as I predicted before the season), as they had a differential of 0 by turning it over 22 times and forcing 22 turnovers, but that was with a hyper-conservative offense designed to limit turnovers.
The Bears recovered 14 fumbles, which is unlikely to repeat itself this year.
I say that because the Bears were very lucky when it came to fumbles last year. They led the NFL with 14 fumble takeaways, and recovered over 65% of the possible fumbles they could, which was 2nd in the league. Fumble luck has been historically shown to be fluky, as every team ends up around 50% over time, so the Bears can’t count on that repeating (side note: this is part of the reason why the study I linked above with a 65% correlation between turnovers and winning found that interceptions specifically accounted for the majority of that).
Playmakers Needed
So here’s where we’re at:
- If the Bears want to win more games, they need to force more turnovers (and/or turn the ball over less, but we’re focusing on the defense for now).
- The Bears are likely going to recover fewer fumbles this year than they did in 2017.
Thus it stands to reason that the Bears need to get significantly more interceptions, both to make up for the expected lost fumble recoveries and to generate a positive turnover differential. Where are those interceptions going to come from?
They have three well-established players who don’t really get interceptions in Prince Amukamara (7 in 7 years), Bryce Callahan (2 in 3 years), and Adrian Amos (1 in 3 years). All three have been starters for several years and consistently don’t catch opposing passes. Some slight improvement could be hoped for here, but it’s not realistic to think that this trio will grab more than 4-5 interceptions (combining the best season of all three would give you 6).
The other two starters in Chicago’s secondary, then, are probably going to have to be the primary drivers of any interception improvements. Kyle Fuller has 8 interceptions in his 3 year career and had 2 interceptions in 2017. He was among the league leaders in passes deflected last year, and turning a few of those into interceptions would be helpful. Fuller had 4 interceptions as a rookie in 2014, so that’s a realistic high-end expectation for him in 2018.
That leaves us with Eddie Jackson, who had 2 interceptions as a rookie in 2017 and was just a split second away from making several more. He showed the ability to be a ballhawk in college, as he caught 6 balls in 2015, and getting up near that total in 2018 would be a huge boon.
If the trio of Amukamara, Callahan, and Amos can combine for 4 interceptions and Fuller and Jackson can each get 4, that would give the Bears 12, which is already a nice improvement from the 8 they’ve had for three straight seasons. A few more from linebackers (who have averaged 2 int/year since Fangio came to Chicago) and/or backup members of the secondary would push them towards the middle of the pack in the NFL and might just help them win them a few more games.
No matter where they come from, the Bears need to find a way to grab more interceptions in 2018. If they don’t, the improvements to their roster won’t make as much of an impact in the wins column as they would like.
