Players who need to step up to fill the holes created by free agency

Casey Hayward, Virgil Green and many other lesser-known players have a big opportunity to fill the roles vacated by this spring's key departures in NFL free agency.

Free agency has burned down to its dying embers. A few recognizable names remain available (Michael Crabtree, Stevan Ridley, Stefan Wisniewski, etc.), but for the most part NFL teams have their depth charts in order ahead of next month's draft.

The past few weeks have been overloaded with analysis of the players who have changed teams, either through free agency or trade. Less attention has been given those who were left behind.

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The players below all will have an opportunity to fill the roles vacated by this spring's key departures. They will be assessed closely this off-season as teams ponder their next move.

• Sealver Siliga, DT, Patriots: In losing Darrelle Revis and Brandon Browner to free agency, the Patriots are putting a lot on the cornerbacks held over from last season's team: Logan Ryan, Alfonzo Dennard and Super Bowl hero Malcolm Butler. If the hope is that a stout front seven can make up for the losses on the back end, though, recovering from the departure of veteran Vince Wilfork could be just as critical.

Enter Siliga, a big-bodied interior lineman who showed potential as a run-stuffer in limited action last season. At 6'2" and 325 pounds, Siliga is the heir apparent to Wilfork's role up front, along with fellow 325-pounder Alan Branch.

"There may have never been anyone at his position with as much strength, toughness, intelligence, instinctiveness and athleticism," Bill Belichick said in a statement after Wilfork signed with Houston. "He is the best defensive linemen I ever coached, an all-time great Patriot whose place on our team will be missed but whose remarkable career as a Patriot will be remembered forever."

No pressure, Sealver.

[daily_cut.nfl]• Virgil Green, TE, Broncos: Earlier this month, Denver handed matching three-year contracts to Owen Daniels and Green worth a combined $20.4 million total—about $3.6 million less than the guaranteed money Julius Thomas got from Jacksonville on a five-year deal. Denver never seemed to have much interest (or ability) to keep Thomas at his going rate, but his loss frees up a healthy number of targets in the Peyton Manning-led passing game.

Daniels has become Gary Kubiak's personal Phishhead, following the coach from stop to stop around the country—Houston through 2013, Baltimore last season and now Denver. He caught 48 passes and scored four times last season.

Green is something of an untapped talent. Coming off a six-catch season, the 2011 seventh-round pick is in line for a substantial uptick in targets. The Broncos will ask Green to remain a solid blocker while joining Daniels in keeping the tight end spot a viable weapon for Peyton Manning.

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• Marlon Brown, WR, Ravens: Bank on seeing a lot of mock drafts send a receiver to Baltimore in the coming weeks. With Torrey Smith now in San Francisco, the Ravens' depth chart at that position looks unsettled, at best, with Steve Smith and a bunch of question marks left for Joe Flacco to throw to.

The Ravens are banking on Brown (along with Kamar Aiken and 2014 rookie Michael Campanaro) to become a more consistent contributor in his third season. He came out of nowhere as a rookie in 2012 to catch 49 passes and score seven touchdowns, then slipped back to 24 grabs and zero touchdowns last season. At 6'5", he's the tallest of Baltimore's remaining receivers, which could be noteworthy for new offensive coordinator Marc Trestman, who milked all he could out of towering targets Brandon Marshall and Alshon Jeffery in Chicago.

• Josh Huff, WR, Eagles: "What's he going to do? That's exactly the point. Nobody knows what this guy is capable of!"

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George Costanza said those words about fake George Steinbrenner, but they work just as well in reference to Chip Kelly's off-season approach. Maybe Kelly trots out Riley Cooper, Jordan Matthews and Huff in three-receiver sets next September; maybe he puts three quarterbacks in the same backfield and runs a quintuple option. Who knows?

Assuming Kelly takes the more conventional route, Huff, not Matthews, could be ticketed for Jeremy Maclin's vacated role in the offense. Matthews has the size advantage (6'3" to Huff's 5'11"), but Kelly might prefer to keep Matthews in the slot. If so, Huff could be first up as Maclin's replacement.

The obvious factor in Huff's favor: He played for Kelly at Oregon.

• Casey Hayward, CB, Packers: When the Packers used a second-round pick on Hayward back in 2012, they no doubt envisioned the day would come when he stepped into the role of a full-time starter. After Tramon Williams and Davon House bolted for Cleveland and Jacksonville, respectively, Hayward's time is now.

Is he ready? As a nickel back from 2012-14, Hayward displayed a knack for making plays—he had six interceptions as a rookie and added three more last season, along with two defensive touchdowns. On the other hand, he has played just 558 snaps over the past two years, mainly due to a 2013 hamstring injury. That's about 500 fewer snaps than Williams handled in 2014 alone.

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• Nat Berhe/Cooper Taylor, S, Giants: Look, someone has to play safety for the Giants. Antrel Rolle handled one starting spot there last season, while Stevie Brown and Quintin Demps shared the other. Rolle has since signed with Chicago, while the latter two are still out there in free agency (and thus, could still re-sign with the Giants).

All that remains on the depth chart at safety for now, however, are Berhe and Taylor, who combined for just 32 snaps—all Berhe's—in 2014.

"They're going to get a chance to compete," general manager Jerry Reese said of his inexperienced safety pair. "Cooper obviously has to stay healthy, but I think both of those guys are going to get a chance to compete for that position."

• Theo Riddick, RB, Lions:Reggie Bush's injury issues accelerated Riddick's role in his second year in Detroit. With Bush in San Francisco, Riddick could earn a permanent job as a complement to Joique Bell in the backfield. Riddick averaged 9.3 yards on his 34 catches last season, a full three yards better than Bush's per-catch average.

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"When you have a guy like Theo Riddick who can make a difference in the passing game, that brings value to your team," GM Martin Mayhew said at the combine, via ESPN.com. "When Joique Bell plays between the tackles running for us, it's big and he does a good job catching balls out of the backfield as well."

Lions running backs combined for 108 receptions on 159 targets last season. Matthew Stafford will lean on that group as his safety net again in 2015, meaning Riddick might be headed toward a breakthrough.

• Xavier Su'a-Filo, G, Texans: The Texans received high marks when they nabbed Su'a-Filo atop Round 2 of last year's draft. The UCLA product looked ready to step in and play immediately as a rookie.

Oops.

Su'a-Filo was unable to crack Houston's regular offensive line rotation, then a back injury kept him out of any opportunities for evaluation late in the year. Now that longtime center Chris Myers has been let go, Ben Jones projects as the Texans' new man in the middle, which leaves Jones's guard position available for Su'a-Filo. Can he make that switch stick?

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•T.J. Fatinikun, DE, Buccaneers: Digging fairly deep into the pile on this one. An undrafted player out of Toledo last year, Fatinikun worked his way into Tampa Bay's defensive line rotation over the second half of the season, swiping some snaps from an underperforming Michael Johnson. With Johnson now back in Cincinnati, the Buccaneers have an opening on the edge.

Jacquies Smith, who was a pleasant surprise with 6.5 sacks, should man one starting defensive end spot. The other is up for grabs, at least with the draft approaching. Fatinikun may not be ready for an every-down role, but he should see plenty of chances as a rotational option.

• Justin Bethel/Jerraud Powers, CB, Cardinals: The Cardinals could have an entertaining training camp battle on their hands between Bethel and Powers, with the starting job that formerly belonged to Antonio Cromartie on the line. Cromartie rejoined the Jets (and Darrelle Revis) this month, opening the cornerback spot opposite Patrick Peterson in Arizona.

Powers is the odds-on favorite, having started on the outside first for the Colts and then for the Cardinals prior to Cromartie's arrival. He spent last season manning the slot, but if Tyrann Mathieu successfully returns from his season-ending knee injury, he could allow Powers to move back outside.

However, Bethel is an intriguing wild card. Bruce Arians hyped him up prior to the 2014 season, and he has earned back-to-back Pro Bowl trips as a special teams player.