The Bears were supposed to field a potentially generational defense in 2019. Instead, the unit was an above-average group that led Chicago to an 8-8 record. They finished eighth in the league in yards allowed per game and were fourth in points allowed per game (18.6).
In an ordinary year with an even ordinary offense to complement this defense, the Bears probably would've been a playoff team. But it would be unfair to say Khalil Mack & Co. were anywhere near as dominant as they were in 2018.
Here's Part 2 of our Season Grades. Check out Part 1 (offense) here.
Defensive Line: B
All things considered, the Bears' defensive line played well in 2019. The heart and soul of the front-four, Akiem Hicks, played just 191 snaps this season because of an elbow injury suffered in Week 5 against the Raiders. He returned for the Packers game in Week 15 but was nowhere near 100%. That said, when Hicks was healthy, he was as dominant as ever.
Eddie Goldman had the kind of season we've come to expect from the fifth-year nose tackle. He was strong and stout in the middle of the Bears' defensive line and allowed Chicago's second-level defenders to run free and make plays. His box score doesn't tell the whole story of how valuable he is to this defense; it never has. He finished 2019 as the Bears' eighth-highest graded defender via Pro Football Focus, but his true value extends beyond the analytics. Chicago's defense would be in big trouble if it lost Goldman for an extended period of time.
Bilal Nichols, Nick Williams and Roy Robertson-Harris all logged between 445 and 544 snaps in 2019 and proved to be solid, even if unspectacular.
Williams was one of the feel-good stories from 2019. The 29-year-old free-agent-to-be enjoyed a career-year with six sacks and at times seemed unblockable as an interior penetrator.
“You want to show, especially teams that cut you, that just put you out,” Williams said, “you want to show them that they made a mistake. I think I did that this year. I played some good football and did some good things on the football field.”
The 2019 season began with such high expectations for a linebacker group that featured the likes of Khalil Mack, Leonard Floyd, Roquan Smith and Danny Trevathan. But much like the Bears' season as a whole, they underachieved.
It starts with Mack, who's held to a different standard. He finished the season with the highest Pro Football Focus grade on the team, which suggests he had a good year. But he was brought to Chicago to be an impact pass-rusher, and his 8.5 sacks this year didn't cut it. It was his least-productive season since his rookie year in 2014.
This isn't to say Mack was a total disappointment. He's still the present and future of this defense. But if the Bears want to be a Super Bowl contender, Mack has to be a Defensive Player of the Year candidate. He wasn't that in 2019.
What's worse, however, was the lack of sack production from his running-mate. Floyd has been a big letdown since coming to Chicago as the ninth overall pick in the 2016 NFL draft. He was supposed to be a freakishly athletic pass-rusher, but after four seasons and just 18.5 career sacks, the ship has sailed on that scouting report. He had a career-low three sacks in 2019.
The most bizarre situation of this season was Smith's unexplained deactivation prior to Week 4's Vikings game. His play was already falling below expectations and he didn't start turning the corner until Week 10 against the Lions. Unfortunately, Smith's year ended early because of a torn pec in Week 14. He was trending in the right direction, however, and with a full offseason to make a full recovery, he should be one of the centerpieces of the defense again in 2020.
Trevathan, who's scheduled to hit unrestricted free agency this offseason, was playing up to his career-standard prior to his gruesome arm injury in Week 10. It's unlikely he'll be back in 2020, and it's in large part because of the emergence of Nick Kwiatkoski, who shined as a starter once his number was called.
Kwiatkoski is set to hit the open market as well, but he has to be a priority for general manager Ryan Pace. He was the Bears' highest-graded linebacker aside from Mack. He finished 2019 fourth on the team in tackles, which is remarkable considering he didn't play meaningful reps until Week 10. Had he started all season, he would've led the team in that category by a wide margin.
And let's not forget the late-season performance of Kevin Pierre-Louis, who filled in for Smith in Week 14 after he exited with his pec injury. Pierre-Louis finished the last three games as one of the most violent and active Bears defenders. He wasn't perfect and had some lapses in judgment (see his running into the punter penalty in Week 16 against the Chiefs), but he finished 2019 with four strong games and an end-of-year grade of 90.5 from Pro Football Focus.
Pierre-Louis, like Kwiatkoski and Trevathan, is a free agent this offseason.
Kyle Fuller and Prince Amukamara were fine in 2019. They really were. But what they didn't do was create turnovers at the same rate they did in 2018, and that regression was a big part of the Bears' letdown this season.
Fuller's interception total dropped from seven to three, while Amukamara dipped from three to zero. That's a difference of seven turnovers, which is significant considering the Bears as a team managed just nine interceptions all year.
Amukamara is one of the more likely veterans to be a salary-cap casualty this offseason. The Bears will save $9 million by cutting ties and it's a move that makes sense, even if Amukamara's proven to be a strong presence in Chicago's secondary. He simply wasn't a difference-maker in 2019, and at 30 years old, his best years are likely behind him.
Kevin Tolliver, Jr., who joined the Bears as an undrafted free agent in 2018, had a productive second season with the team. He logged 175 snaps and gave Chicago a glimpse at what he could do as a potential starter in 2020. The Bears could do a lot worse than Tolliver, who ended 2019 with 13 tackles and two pass breakups.
Rookie Duke Shelley played just eight snaps on defense in what was an incomplete rookie season for the sixth-rounder.
Much like the cornerback position, the Bears' safeties were solid in 2019 with the exception of turnovers. Eddie Jackson was especially disappointing in this department. He managed just two interceptions after snagging six in 2018. Jackson had three defensive touchdowns in 2018 but had zero this year.
Jackson's reputation led to a Pro Bowl nod despite his play probably not warranting it. Consider it a down year for him. His resume has enough high-end production to erase any concerns that he isn't the player Bears fans thought he was entering the season.
One of the best value players on the Bears' defense this year was Ha Ha Clinton-Dix, who signed a one-year, $3 million contract with Chicago in free agency last offseason. He rewarded Pace's decision by having the third-most tackles on defense, two interceptions and a defensive touchdown.
Clinton-Dix was the Bears' second-highest graded defender via PFF this season and will be a priority contract for Pace to get done early in the offseason. Otherwise, they'll be left searching for his replacement much like last year when they signed Clinton-Dix to fill the void left by Adrian Amos.
Jackson and Clinton-Dix were ironmen this season. They played the second and third-most snaps of all Bears' defenders in 2019.Click here to download the new MyTeams App by NBC Sports! Receive comprehensive coverage of the Bears.