The Chicago Bears in 2015 tried to make due at the inside linebacker position with Shea McClellin and Christian Jones, a position brand new to both players.
To the surprise of few, the results were mediocre at best. The duo combined for 167 tackles and made a number of plays, yet overall, each showed his inexperience at the position. In addition, neither played downhill, typically a prerequisite for a successful 3-4 inside linebacker.
As a result, coordinator Vic Fangio was forced to experiment by rotating a number of different players on game days. At different points, Jonathan Anderson, LaRoy Reynolds and John Timu were all part of the inside linebacker rotation.
At the end of the day, despite some promising outings from Anderson and Timu, the Bears will aggressively pursue upgrades at ILB this upcoming off-season.
With that in mind, let's take a closer look at the top free-agent inside linebackers that will soon hit the open market.
Danny Trevathan, Denver (6-1, 240) Age: 26
Trevathan was one of the best linebackers in the NFL last season. He showed vision and aggressiveness against the run, while in coverage he posted 6 pass breakups and 2 interceptions, one of which he returned for a touchdown. The leader of arguably the best defense of this decade, Trevathan is a premiere option for the Bears, who need a north-south linebacker of his caliber. He was drafted by John Fox and admitted this week he'll likely speak with the Bears this off-season. If Fox and GM Ryan Pace can pursuade the 26-year-old Trevathan to leave Denver, it will be an enormous coup.
Jerrell Freeman, Indianapolis (6-0, 240) Age: 30
Freeman has been a full-time starter for the Colts the past four seasons and is coming off his best pro campaign. Before 2015, he wasn't known as a top-tier run stuffer but he was exceptional against the run last year, pacing the rest of the league's inside linebackers. He's sometimes sketchy in coverage - he gave up 3 TDs last season, while opposing QBs had 101.0 rating against him - but Freeman brings the thump and power currently missing from Fangio's defense.
Derrick Johnson, Kansas City (6-3, 242) Age: 33
Johnson has been a staple in Kansas City's defense since the Chiefs selected him in the first round of the 2005 NFL Draft. The 11-year veteran is coming off one of his best seasons in 2015, compiling 116 tackles, 4.0 sacks, 8 PBUs, 2 INTs and 2 forced fumbles. Even at 33, Johnson still has plenty left in the tank. He's expressed his desire to stay in Kansas City but if he hits the open market, the Bears would be wise to pursue him on a short-term deal.
Rolando McClain, Dallas (6-4, 255) Age: 27
McClain is not the best run defender but he's outstanding in coverage. Opposing QBs had a 67.0 rating last year when throwing at McClain, which is very good. He also added 2.0 sacks, 3 pass breakups and 1 INT, which he returned for a TD. McClain is a one-dimensional player, so he won't cost as much as the top three ILBs on this list.
Zach Brown, Tennessee (6-1, 248) Age: 26
A former 2nd-round pick in 2012, Brown is considered a bust in Tennessee. He has struggled against the run his entire four-year career and, as a result, was benched last season. On the flip side, Brown is very good in coverage, as opposing QBs had just a 60.4 rating when throwing at him last year. He's only 26, so there's plenty of time for improvement and Brown will come very cheap.
Tahir Whitehead, Detroit (6-2, 242) Age: 26
Whitehead was pretty solid for the Lions after being inserted into the starting lineup midway through last year. He showed toughness against the run and wasn't a liability in coverage. He's played 4-3 OLB his entire career, so there would be a learning curve for him to overcome in Chicago, but this 26-year-old talented kid shouldn't be overlooked.
Vincent Rey, Cincinnati (6-0, 255) Age: 28
Rey led the Bengals in tackles (98) last season and served as the glue for one of the league's toughest defenses. He doesn't excel in any area of his game but he's solid all-around. He's only played in a 4-3 but his heavy-handed playing style might be better suited for a 3-4 defense.
Demario Davis, N.Y. Jets (6-2, 239) Age: 27
A starter for the Jets the past three seasons, Davis took a step backward last year, struggling in both areas of his game. He was particularly suspect in coverage, allowing an 80.0 completion percentage and 126.8 QB rating against. Davis has played well in the past, so the potential is there, and at just 27 years old, maybe Fangio and company can right the ship.
Craig Robertson, Cleveland (6-2, 234) Age: 28
The Browns were so high on Robertson last year, the gave him a second-round RFA tender. He struggled with a knee injury, which limited him as a run defender and forced him to miss four games, but he was solid in coverage. Still young, Robertons might be worth a look as a rotational option.
Keenan Robinson, Washington (6-3, 238) Age: 27
Sean Spence, Pittsburgh (5-11, 231) Age: 26
Jamari Lattimore, N.Y. Jets (6-2, 229) Age: 27
Audie Cole, Minnesota (6-5, 248) Age: 27
David Hawthorne, New Orleans (6-0, 246) Age: 31
Erin Henderson, N.Y. Jets (6-3, 244) Age: 30
Jerod Mayo, New England (6-1, 250) Age: 30
Sean Weatherspoon, Arizona (6-2, 244) Age: 29
Kelvin Sheppard, Miami (6-2, 249) Age: 28
Danny Trevathan or Jerrell Freeman: The biggest need for the Bears this off-season is at inside linebacker, a pivotal position in Fangio's defense. As such, Pace needs to throw a healthy chunk of change at either Trevathan or Freeman, both of whom would immediately stabilize Chicago's front seven. Both players are beasts against the run with much-needed experience and leadership. Trevathan is coming off a Super Bowl championship and is close with John Fox, so the Bears have a leg up over the rest of the league in potentially landing him.
There isn't a lot of talent in this inside linebacker group, nor in the draft, but a decent Plan B is Zach Brown. He's solid in coverage and is young enough to continue developing against the run.