Negotiation time: Teams with the most to lose in upcoming free agency

Many NFL teams enter free agency with a Christmas list of sorts, looking to spend wisely (hopefully) to improve the look of their franchises. However, plenty of teams are just as concerned about losing certain players through that same mechanism. If things don't work out from a cost/benefit standpoint, a team can be left without one or more of its most valuable assets.

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These teams have the most to lose in the upcoming free agent derby. The 2015 NFL salary cap has been confirmed at 143.28 million, and all approximate team salary cap estimates come from OverTheCap.com.

Dallas Cowboys (2015 cap space: $18,672,965)

[daily_cut.nfl]​At the top of Dallas's list of concerns is the round robin between WR Dez Bryant and RB DeMarco Murray. The Cowboys planted the franchise tag on Bryant at a cost of $12.823 million, which likely limits what the team can do with other players, and unless Murray takes a serious discount to play behind the NFL's best run-blocking line, he'll hit the road. There can be some relief by designating cornerback Brandon Carr as a post-June 1 cut—the team would get $8 million in cap room back on Carr's fairly monstrous $12,717,000 cap hit, especially given his sub-par performance.

The Cowboys also have two of their primary outside linebackers in Bruce Carter and Justin Durant to consider, and there's right tackle Doug Free and inside linebacker Sean Lee in the mix. Both Free and Lee have dealt with injuries recently—Lee, who can't seem to stay healthy, is particularly vexing because he's so good when he's not injured. Tagging Bryant made the most sense, but taking chances at running back in the long term and losing key members of a defense that was held together with spit, baling wire and great coaching in 2014 could lead to a quick downturn.

Denver Broncos (2015 cap space: $29,399,342)

The Broncos copied the Cowboys by placing the franchise tag on their best and most important receiver—Demaryius Thomasgot the tag, giving Denver a bit more flexibility. Of course, the elephant in John Elway's room is Peyton Manning's status—should Manning retire, the Broncos would have $21.5 million in cap space for the 2015 season, though they'd have plenty of other questions to answer, if that's the case.

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Then there's the question of TE Julius Thomas. Last season, Thomas led the team with 12 touchdowns on just 43 catches and 60 targets, and any player who's good for a touchdown once every five targets is going to get some fairly decent money on the open market. Will NFL teams see through the idea that he was catching those passes from Manning, and may have deflated numbers in most other systems? Perhaps, but there are enough teams in need of big targets, and with enough of a belief in their own passing games, rightly or not. Beyond Manning and the two Thomases, there is also defensive tackle Terrance Knighton, left guard Orlando Franklin, linebacker Nate Irving and safety Rahim Moore among the higher-talent players who must either be retained or replaced through other channels.

Detroit Lions (2015 cap space: $18,443,192)

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The Lions announced on Monday that they will not place the franchise tag on Ndamukong Suh, not that they could have taken the $26.7 million single-year cap hit anyway. One major issue for the Lions is that they have $38,279,250 in 2015 cap money tied up in two players—QB Matthew Stafford and WR Calvin Johnson. Team president Tom Lewand and general manager Martin Mayhew have said all the right things about the Lions somehow keeping Suh, but without a major clearing of the team's mid-level cap casualties, it doesn't make a lot of sense. Suh is likely to get a contract from some team in the same vicinity of J.J. Watt's six-year, $100 million deal with $51.8 million guaranteed. Watt's first year of the deal has a $21,969,000 cap hit, so let that be instructive.

With Suh likely out of the picture, it's possible that the team will ignore Nick Fairley's history of injuries and off-season incidents, hoping that he can become the face of Detroit's defensive line. Tackle C.J. Mosley is also a free agent, and he performed well in a reserve role last season. The Lions have already released running back Reggie Bush, and they have cornerbacks Rashean Mathis and Cassius Vaughan as impending free agents. Mathis enjoyed a bit of a renaissance season under first-year defensive coordinator Teryl Austin.

Green Bay Packers (2015 cap space: $33,109,792)

The two big names for the Packers to consider are receiver Randall Cobb and offensive tackle Bryan Bulaga. Cobb was primarily a slot receiver in 2014, but he led the league with 12 slot touchdowns on 106 targets, according to Pro Football Focus, and that could put him in line for a contract that could leap to $8 million per year for the right team. The right team could be the Packers, and Aaron Rodgers would of course love to have Cobb back. Rodgers would also love to have Bulaga back; he was a cornerstone in the offensive line Rodgers called the best of his career, allowing just four sacks and two hits in 1,091 snaps throughout the 2014 season.

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The Packers will also have to decide their future with cornerback Tramon Williams, who has played at an All-Pro level at times over the last few seasons but fell short of his own standards, allowing eight touchdowns and a 101.7 opposing quarterback rating in 2014. And there's nose tackle Letroy Guion, who played pretty well in the middle of Green Bay's defensive line. If Guion cuts loose, it's possible that the Packers could re-sign B.J. Raji, who missed the entire 2014 season with a biceps injury. No matter what the Packers do in free agency, they know there's a lot of catching up to do with a defense that underperformed last season. Cutting linebacker A.J. Hawk was the first step. Designating Julius Peppers as a post-June 1 cut and picking up $9.5 million in cap space could be another, but all signs point to Peppers returning to the team at his 2015 salary.

New York Giants (2015 cap space: $24,232,638)

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The Giants have placed the franchise tag on defensive end Jason Pierre-Paul, which ties up $14.8 million in cap space unless the two sides can come to terms on a longer deal by July 15. Pierre-Paul was the team's first-round draft pick in 2010, and he rebounded nicely in his contract year for 12.5 sacks in 2014 after a total of 8.5 sacks in the two seasons before. Pierre-Paul is a tremendously valuable player when healthy, but that takes a lot of Big Blue's flexibility away—and this is a team that needs roster improvement at several different positions.

The Giants have already released end Mathias KIwanuka, freeing up $4.25 million in cap space, but adding more than $2.5 million to their dead money. Three safeties—Antrel Rolle, Stevie Brown and Quintin Demps—are up for free agency, as are guards James Brewer and John Jerry. The Giants were hoping for more than they got from cornerback Walter Thurmond on a one-year deal, but he was lost for the season after two games to a torn pectoral. If the Giants can't get Pierre-Paul to agree to a deal that makes the tag a non-issue, they could be sailing through the 2015 season much like they did in '14, and after declining win totals over the last three seasons, that's not a good thing.

New England Patriots (2015 cap space: -$7,624,313)

Only the New Orleans Saints have a bigger negative cap total than the defending Super Bowl champions—actually, the Saints and Patriots are the only two teams in the red right now. This is estimating Darrelle Revis' $25 million cap number as part of the two-year deal at club option he's currently under; obviously, the hope is that Revis will sign a long-term contract and ease that pressure. He has a $12 million roster bonus due March 9, so it behooves both sides to get something done. Revis is a perfect fit in Bill Belichick's system. Linebacker Jerod Mayo, whose 2014 injury allowed Jamie Collins to step up and be a star, has an injury guarantee in his contract that would cost the team $4.5 million if they cut him before he was deemed healthy.

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So, with all that, where might the Patriots cut corners to get under the cap, have enough for their rookies AND make a few moves? New England could save over $8 million if they cut Vince Wilfork, and as unthinkable as that seems, Belichick hasn't exactly been sentimental about keeping his long-time priority guys when they are no longer priorities. Guard Dan Connolly, running backs Shane Vereen and Stevan Ridley, and linebacker Akeem Ayers are second-level players the Pats could deem invaluable for the right price. One player on the market who is definitely a priority? K Stephen Gostkowski, who received the team's franchise tag. 

San Francisco 49ers (2015 cap space: $6,242,889)

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This could get ugly. The 49ers have jettisoned their head coach, offensive coordinator and defensive coordinator for new (and less impressive, in the minds of many) options, and now, they'll have to make some major decisions regarding the futures of several key players. RB Frank Gore will likely move along, as he's reportedly looking to make $4 million per season, and the 49ers have Carlos Hyde all ready to go. Guard Mike Iupati is expected to have several suitors around the league despite the seven sacks he allowed in 2014, but receiver Michael Crabtree may have to take a discount, as he hasn't been the same player since he injured his Achilles' tendon in 2013. Cornerback Chris Culliver, who had an excellent 2014 season, is another consideration.

So, with little left in their books to spend, who's likely to get the boot? According to Over The Cap, the 49ers would save $9,754,000—the full 2015 value of Aldon Smith's contract—if they released the talented but troubled pass-rusher. Linebacker Ahmad Brooks is another candidate for release; San Francisco would get $4,706,250 in cap space if they designated Brooks as a post-June 1 cut. Receiver Stevie Johnson, who caught 35 passes for 435 yards and three touchdowns in 2014, will either restructure his contract or be sent packing, and his release would free up another $6,025,000.There are several other veterans, including receiver Anquan Boldin and linebacker Patrick Willis, whose releases could free up millions of cap dollars. It's up to the questionable new regime in the Bay Area just how many iconic names could be gone in favor of a rebuilding, but one thing's for sure—the 49ers are butting up against it this offseason, and they could pay dearly when it's time to be competitive.