In 2015, the Chicago Bears defensive line was hindered by injuries, and one lunatic.
Jeremiah Ratliff proved to be a danger to the entire organization and was released in Week 7, Ray McDonald was too busy being charged with rape and false imprisonment, while Ego Ferguson and Eddie Goldman finished the year on IR.
Mitch Unrein emerged as legitimate rotational 5-technique with strong ability against the run, yet Will Sutton once again disappointed. Jarvis Jenkins started the season strong but his overall impact was minimal, while Bruce Gaston, Greg Scruggs and D'Anthony Smith were little more than roster fill-ins.
Clearly the Bears need more consistency and production from the defensive line, so expect GM Ryan Pace to add fresh blood in the trenches this off-season.
With that in mind, let's take a close look at the top defensive linemen who will be available in free agency.
Muhammad Wilkerson, N.Y. Jets (6-4, 315) Age: 27
Wilkerson is the top free-agent defensive lineman on the market. He's an absolute beast against the run and had 12.0 sacks, with 44 QB hurries, last season. He's one of the biggest reasons the Jets' defense has been nearly impossible to run against the past five years. Wilkerson broke his leg in the season finale last year but that's not going to reduce his price tag. If the Bears want to go big - he'll likely command $12M-$15M per season - then Wilkerson is their guy. Update: The Jets placed the franchise tag on Wilkerson.
Malik Jackson, Denver (6-5, 293) Age: 26
Jackson is one of the best pass rushing 3-4 defensive ends in the league. He had 5.0 sacks and 45 QB hurries last year, and was a beast in the playoffs, particularly the Super Bowl. The Bears lacked interior pass rush last year, the area in which Jackson excels. He was drafted by Bears head coach John Fox, so there's familiarity and trust already built in to that relationship. Fox should use his influence to bring Jackson to Chicago.
Nick Fairley, Los Angeles (6-4, 308) Age: 28
Fairley had just 0.5 sacks for the Rams last season yet he played very well against the run in a part-time role. When motivated, Fairley can be a disruptive force and has the potential for 5 to 6 sacks per season. He's still just 28 and has plenty of good seasons ahead of him.
Damon Harrison, N.Y. Jets (6-4, 350) Age: 27
Harrison doesn't provide anything as a pass rusher - he has just 1.5 total sacks during his four-year career - but he's one of the best run-stopping nose tackles in the game. He's a massive human being who can occupy blockers and eat up space in the middle of the trenches. With "Snacks" on board, the Bears would instantly become one of the best run defenses in the NFL.
Jaye Howard, Kansas City (6-3, 301) Age: 27
After dealing with injuries his first two years in the league, Howard has been healthy the past two seasons and has emerged as one of the NFL's premiere run defenders. He's relatively small for a 5-technique but he's extremely powerful, and even added 5.5 sacks last season. Howard is only 27 and he'd be great value as a long-term option along Chicago's defensive line.
Ian Williams, San Francisco (6-1, 305) Age: 27
Williams has been injured for most of his career but was healthy in 2015 and showed his prowess as a run stopper. Bears defensive coordinator Vic Fangio is very familiar with Williams, having coached him for four seasons with the 49ers. His extensive injury history means he'll come cheap and he might be worth an incentive-laden short-term contract.
B.J. Raji, Green Bay (6-2, 337) Age: 30
Raji is still a quality run defender when healthy but he's been banged up the past two seasons. He offers nothing as a pass rusher and turns 30 in July. The Bears don't need this cheesehead.
Terrance Knighton, Washington (6-3, 354) Age: 30
Knighton thought he would break the bank in free agency last year, potentially from the Bears and his former head coach, but he overestimated his value and was forced to sign a one-year deal with the Redskins. He's enormous and his weight has always been an issue. He was decent against the run last year but nearly invisible as a pass rusher. He also turns 30 in July, meaning he's a short-term option at best.
Haloti Ngata, Detroit (6-4, 345) Age: 32
For a three-year stretch in Baltimore, Ngata was an unstoppable force at nose tackle. Yet he's faded late in his career and has just 6.0 sacks the last three years combined - compared to 15.5 total sack the previous three years. He also struggled to find consistency as a run defender and at age 32, he's not likely to get better going forward.
Cedric Thornton, Philadelphia (6-4, 309) Age: 28
Thornton is one of the best run-stuffing 5-technique defensive ends in the NFL. He offers little as a pass rusher - he has 4.0 sacks the past four years combined - but he would be a huge boost to Chicago's run defense on 1st and 2nd down.
Henry Melton, Tampa Bay (6-3, 290) Age: 29
Bears fans are well aware of Melton's prowess on passing downs. He's still a quality pass rusher but he's a liability against the run. Still, the Bears run a hybrid defense in which Melton could excel as a part-time pass rusher on passing downs. He'd also come very cheap and hasn't missed a single regular-season contest the past two years.
Akiem Hicks, New England (6-5, 324) Age: 26
Letroy Guion, Green Bay (6-4, 322) Age: 29
Mike DeVito, Kansas City (6-3, 305) Age: 32
Kendall Reyes, San Diego (6-4, 300) Age: 26
Kevin Williams, New Orleans (6-4, 311) Age: 36
Corbin Bryant, Buffalo (6-4, 300) Age: 28
Al Woods, Tennessee (6-4, 307) Age: 29
Steve McLendon, Pittsburgh (6-3, 310) Age: 30
Sammie Lee Hill, Tennessee (6-4, 328) Age: 29
Pat Sims, Cincinnati (6-2, 340) Age: 30
Red Bryant, Arizona (6-4, 323) Age: 32
Jaye Howard: Wilkerson, Jackson and Harrison are outstanding options but all three are going to cost an arm and a leg. Howard is only 27 and is just now entering his prime. He's agile and powerful, with the ability to two-gap against the run and collapse the pocket in the face of opposing quarterbacks. Howard isn't as big of a name as some of the others on this list, so the Bears should be able to sign him at a cap-friendly price. His presence at 5-technique, as well as 3-technique on passing downs, would be a big boost to Chicago's defensive line.
A solid Plan B is Cedric Thornton. He's a one-dimensional player but his run-stopping prowess is something else. He's played in a 3-4 for most of his career and knows how to eat up space, shed blocks and make tackles. He'd be a solid secondary option.
In terms of a pure pass rusher, Henry Melton should not be ignored. He's been relatively healthy the past two seasons and had 2.0 sacks and 9 QB hits in limited action last season. He'll command just the veteran minimum and could add the pass rush Chicago desperately needs on 3rd down.