Washington could have a big hole to fill at the heart of its defense. Free agency starts next week and all three of Washington’s main inside linebackers this past season are free agents. Reports suggest Washington would like to bring back Will Compton, an exclusive-rights free agent, as the starting Mike ‘backer. Mason Foster played well and formed a strong partnership with Compton down the stretch last season. Logic would dictate the team would like him back too. Keenan Robinson and Perry Riley Jr. are expected to be allowed to test the market.

[Free-agent fits: Defensive linemen | Running backs | Safeties | Wide receivers]

Even if Washington does bring back Compton and Foster, the team lacks depth behind those two. There are a number of good prospects in the draft. The team also has last year’s fifth-round pick, Martrell Spaight, returning after missing almost all of his rookie season. But Washington might opt to open its checkbook and sign a free agent next week.

Big name: Danny Trevathan, Broncos, age 25
Trevathan is coming off a Super Bowl win with the Broncos. Denver has a defense stacked with talent, with a number of free agents to re-sign. Trevathan was their starting inside linebacker alongside Brandon Marshall, a restricted free agent. Trevathan looks set to test the market as the Broncos appear to be focused on bringing back other players first.

Trevathan is a well-rounded, solid player. He isn’t someone who will make spectacular play after spectacular play. But he fits the mold of a tough, hard-nosed football player that Washington GM Scot McCloughan loves. He’s strong against the run and isn’t afraid to take on big blockers, despite his 6-foot-1, 240-pound frame being smaller than most blockers he faces.

Here, the Bengals run a power play right at Trevathan. They pull right guard Kevin Zietler to act as a lead blocker for running back Jeremy Hill.

Trevathan reads the play quickly and approaches the line of scrimmage. He doesn’t shy away from contact, instead positioning himself with good leverage, staying as low as possible to take on the pulling guard.

Trevathan stops the guard at the line of scrimmage and holds the point of attack. Hill is forced to cut back inside, which leads Trevathan to fight for leverage inside.

Trevathan closes the hole, cutting off Hill’s lane. He then sheds the block of the guard and wraps up Hill. Trevathan holds the play to a minimal gain.

He’s more of a run defender, but is capable of holding up in coverage, meaning he has value as a three-down linebacker.

On this play, Trevathan acts almost as an extra defensive lineman. He walks up right to the line of scrimmage and positions himself over the tight end. He appears to be a blitzer, but he’s actually in man coverage on the running back. On third and three, the Steelers run a slant-flat route combination designed to get the back open in the flat for an easy first down.

Trevathan narrowly avoids the traffic created by the wide receiver running a slant route. He keeps his eyes on the back and works to close the gap.

As the back receives the pass, there are still a few yards between the two. Trevathan quickly closes and, most importantly, wraps up the back to prevent the first down.

Missed tackles weren’t as much of an issue last year as they have been in the past for Washington, but they crept in every now and again. Trevathan isn’t a guy who misses tackles. He can be trusted to wrap up and bring down the ball carrier, having missed just seven tackles last year, according to Pro Football Focus. He would bring a winning mentality as well as a physical playing style to Washington’s locker room. He doesn’t turn 26 until the end of March, meaning he should still have plenty of years left too.

Trevathan looks set to be the top free agent inside linebacker. He will likely command a big contract, but fits the profile of what Washington looks for in a linebacker. With age on his side, he could prove worth a big contract. But his services will be in high demand, making it unlikely he’ll land in Washington.

Under the radar: Tahir Whitehead, Lions, 25
Whitehead is an interesting free agent. Having played for the Detroit Lions, he isn’t the biggest name. He has suffered with injuries throughout his young career that have held him back too. But the 2012 fifth-round pick offers plenty of good traits that catch the eye. He stands at 6-2, 242, which gives him enough size to survive the battle in the trenches, while also being lean and athletic enough to drop into coverage.

His athleticism stands out against both the run and pass. Here, the Chicago Bears attempt to run a pitch play to Matt Forte. The Bears send their left tackle out to pick up Whitehead and seal him inside.

Whitehead reads and deciphers the play quickly, allowing him to simply run around the tackle and avoid his block attempt.

Whitehead then makes a strong tackle. Forte attempts to cut back inside, but Whitehead attacks his hip and wraps up, bringing him down for a loss.

While that athleticism does stand out against the run, it is more obvious in coverage.

On this play, the Philadelphia Eagles attempt to run a stick route with tight end Brent Celek.

Whitehead aligns with inside leverage to take away routes over the middle of the field. He does a good job staying on top of the route and reacting to the cut to the outside. He turns his eyes back towards the quarterback and undercuts the throw.

Whitehead gets his hand in between the hands of Celek and breaks up the pass.

Here’s a clip of that play:

Later in the season, the New Orleans Saints ran a double move in the red zone off a similar route.

This time, Whitehead is up against Benjamin Watson. Watson runs a stick-and-nod route, faking a stick route to the outside before cutting up the field.

Whitehead takes inside leverage again, effectively bracketing Watson with the safety over the top. However, the safety bites on the double move, leaving Whitehead on his own.

Whitehead smartly recognizes where the route is going and gets his left hand up in the passing lane. Saints quarterback Drew Brees spots this and adjusts his throw to the back shoulder of the tight end.

Whitehead stays with Watson, reading his adjustment and putting his right hand up to block the pass. He gets his hand in between Watson’s and deflects the ball, preventing the touchdown.

Whitehead isn’t a guy who likely will be signed to a large contract on the first day of free agency. However, he has plenty of tools to work with and could be a bargain piece who can compete with Compton and Foster for playing time in training camp. That kind of low-risk signing could give Washington depth at the position, and he could play himself into a starting role.

Mark Bullock is The Insider’s Outsider, sharing his Redskins impressions without the benefit of access to the team. For more breakdowns, click here

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