For the Broncos, tight ends are at one end of the spectrum, and linebackers sit at the other.
This is one position where the Broncos appear to have a good grasp on their starters: DeMarcus Ware and Von Miller on the outside, and Brandon Marshall and Danny Trevathan on the inside. Executive Vice President/General Manager John Elway spoke of Marshall and Trevathan's potential as 3-4 inside linebackers; they fit the size template (the average weight of NFL inside linebackers is 240 pounds), can hold up against the run and have proven themselves in coverage.
The Broncos have some experienced depth behind Marshall and Trevathan, thanks to injuries that knocked both of them -- as well as middle linebacker Nate Irving -- from the lineup.
They learned that Todd Davis has some potential, improving from week to week after starting for Marshall, although he needs some polish in coverage. They learned that Steven Johnson is a solid two-down linebacker, but saw him struggle in coverage, particularly on a touchdown yielded to Cincinnati's Gio Bernard in the Week 16 loss at Paul Brown Stadium. And they have two 2014 draft picks in reserve -- Lamin Barrow and Corey Nelson -- who might fit into the mix somewhere.
Depth is crucial given the injuries sustained by Marshall (mid-foot sprain) and Trevathan (three separate injuries around his left knee) last year. Although the Broncos expect both to be good to go, they will bear close monitoring.
But it's on the outside where more questions linger. Lerentee McCray had some flashes of brilliance, and forced a fumble that turned into a Tony Carter touchdown in Week 17. But Quanterus Smith ended the season on injured reserve with a knee injury, and Shaquil Barrett, a preseason star, is still unproven. With Ware heading into his 11th season, that could lead the Broncos to augment their depth on the outside.
Irving is an unrestricted free agent, while Johnson is a restricted free agent and Marshall is under the exclusive-rights designation. Irving has the added benefit of working as a strong-side linebacker behind Miller earlier in his career, so if the Broncos brought him back, he could be -- at minimum -- a useful utility linebacker who can play three of the four spots in a pinch.
But Irving will attract some interest on the market. He improved when pushed into every-down work, and delivered the requisite thump expected from a 4-3 middle linebacker. His development took more time than expected, and if the Broncos can't retain him, someone else will reap the benefits.
The Broncos will scan the market, as well, and although some other position groups have more pressing needs, the club could fortify this group.
UNRESTRICTED FREE AGENTS:**
OLB JERRY HUGHES, BUFFALO:One-fourth of the Bills' elite front four, Hughes will be an outside linebacker if he transitions to a 3-4 team. After starting just one game in a 2013 season in which he had 10 sacks, he showed no issues as he became an every-down player and 16-game starter last year, matching his sack total and improving against the run. He plays larger than his 254-pound frame, and is active around the football, forcing five fumbles in the last two years.
OLB JASON WORILDS, PITTSBURGH:A feast-or-famine pass rusher, he had 25 percent of his 28 quarterback hurries last year (per ProFootballFocus.com) in one game against the Houston Texans. Worilds has always been an effective pass rusher, but he didn't become a consistent starter until the last two seasons. The 262-pounder still has room for growth -- especially against the run.
OLB PERNELL McPHEE, BALTIMORE:His coveted status despite having just six regular-season starts to his name and situational use on his resume demonstrates the premium placed on pass rushers in today's NFL. McPhee had a career-high 7.5 sacks last year and was credited with 40 hurries by ProFootballFocus.com, which helped create the plus-23.1 pass rush rating the site gave him, which ranked third behind Houston and teammate Elvis Dumervil. But at 280 pounds, he also has the body type to be stout against the run. It seems likely his new team will regard him as more than a situational player.
OLB BRIAN ORAKPO, WASHINGTON:Injury concerns will keep his price down -- he's missed 24 games in the last three years, including the last nine of 2014 due to a torn pectoral muscle. In the 24 games he played in that span, he had 11.5 sacks -- a 0.48-sacks-per-game pace down from his .61-sacks-per-game pace of 2009-11.
ILB ROLANDO McCLAIN, DALLAS:A one-year wonder, or a revived player at the beginning of his renaissance? That depends as much on McClain's status off the field as on it. After last month's reports of a looming four-game substance-abuse suspension, his price will drop -- and his chances for snatching a long-term deal evaporated. He will remain in prove-it mode -- which could benefit the team that signs him, assuming he can avoid the issues that have dogged him to this point.
OLB BRANDON GRAHAM, PHILADELPHIA:He seems likely to move to a team with a 4-3 alignment that better fits his skill set, and could become the every-down player that he was not in Philadelphia, where he started just once in the last two years and only 13 times over his five-season career. As with McPhee, he rates highly in ProFootballFocus.com's measurements -- third among 3-4 OLBs, behind only Houston and McPhee, bolstered by 39 quarterback hurries.
OLB AKEEM AYERS, NEW ENGLAND:A midseason trade from Tennessee changed his fortunes -- and those of the Patriots' defense, particularly with what he contributed in the pass rush. New England established the template and proper use for Ayers; if the Super Bowl winners don't keep him, another team would be wise to use Ayers in the same manner.
OLB LANCE BRIGGS, CHICAGO:At 34, Briggs remains an effective run-stuffer, but age and accumulated wear have caught up to him. He missed 15 games the last two seasons after sitting out just four in his first 10 seasons (2003-12).
OLB KROY BIERMANN, ATLANTA:Working in the 3-4 alignment last year, Biermann started a career-high 15 games last year, finishing with 4.5 sacks, his highest tally since 2009, his second season with the Falcons. He struggled in the first half of the season, but improved in the second, looking more natural in the 3-4 after spending his first six pro seasons in the 4-3.
OLB BROOKS REED, HOUSTON:Solid and steady, his experience in Wade Phillips' defense -- with which he broke into the starting lineup for 11 games as a rookie in 2011 -- should serve him well.
ILB BRUCE CARTER, DALLAS:More effective against the run than in pass coverage or against the run, the reports of a potential suspension for McClain could compel the Cowboys to keep Carter.
OLB JUSTIN DURANT, DALLAS:He was the Cowboys' leading tackler before tearing his biceps at midseason, and was a perfect fit at weakside linebacker in Dallas' 4-3 alignment. But with the afore-mentioned McClain and Carter, the Cowboys have choices to make, and might choose to retain the most cap-friendly option.
OLB JABAAL SHEARD, CLEVELAND:The 264-pounder played through a foot injury that clearly hindered him last year, limiting him to a career-low two sacks. There is a concern over his declining statistics -- his sack total dropped from 8.5 sacks in 2011 to 7 in 2012, and 5.5 over 13 games in 2013. But Sheard's run defense has steadily improved.
OLB SEAN WEATHERSPOON, ATLANTA:It's hard to know what Weatherspoon might do in 2015; he's missed 25 games over the last two seasons, including all 16 last year because of a ruptured Achilles tendon. The Falcons hope he can be as effective in the pass rush as he was in 2012, the last full season he played.
OLB MALCOLM SMITH, SEATTLE:Smith's follow-up to his Super Bowl MVP was a frustrating season in which he receded into the shadows of the Seahawks' defense. He'll start somewhere, but that appears unlikely to be Seattle.
ILB REY MAUALUGA, CINCINNATI:By using him as a situational linebacker, the Bengals were able to minimize his previous issues in pass coverage -- which made him more effective on the occasions when he was forced to drop back.
ILB BRANDON SPIKES, BUFFALO:His struggles in coverage ensure that he will only be a two-down linebacker, but he remains effective as a run stuffer.
OLB JAMES HARRISON, PITTSBURGH:At age 36, he returned to the Steelers and notched 5.5 sacks and 45 tackles in a more limited role than he held during his previous stint. There's still something left in the tank, if he's used situationally.
OTHERS OF NOTE:
OLB Jacquian Williams, N.Y. Giants
OLB Geno Hayes, Jacksonville
OLB Mark Herzlich, N.Y. Giants
ILB Jason Trusnik, Miami
ILB Arthur Moats, Pittsburgh
OLB Dwight Freeney, San Diego
OLB O'Brien Schofield, Seattle
ILB Jasper Brinkley, Minnesota
OLB Shaun Phillips, Indianapolis
ILB Ramon Humber, New Orleans
OLB Sam Acho, Arizona
ILB Akeem Dent, Houston
ILB Jeff Tarpinian, Houston
ILB Nick Bellore, N.Y. Jets
OLB Dan Skuta, San Francisco
ILB D.J. Williams, Chicago
OLB John Abraham, Arizona
OLB Jermaine Cunningham, N.Y. Jets
ILB Colin McCarthy, Tennessee
STREET FREE AGENTS:
OLB Mathias Kiwanuka, ex-N.Y. Giants
ILB A.J. Hawk, ex-Green Bay
RESTRICTED/EXCLUSIVE-RIGHTS FREE AGENTS:
ILB Craig Robertson, Cleveland
ILB Jerrell Freeman, Indianapolis
ILB Michael Wilhoite, San Francisco
OLB Orie Lemon, Tampa Bay
OLB Kaelin Burnett, Tennessee
ILB Jerry Franklin, Saints
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Which linebackers might be a fit for the Broncos in their new 3-4 scheme? Look through the options in free agency in this gallery.