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While a tempting option, placing the franchise tag on cornerback Sam Shields is likely too rich for general manager Ted Thompson and the Green Bay Packers.

Developed in 1992 at the onset of free agency, the franchise tag is a contractual designation that provides NFL teams the once-a-year option of keeping a free agent under a usually heavy one-year monetary obligation.

Shields, 26, will be an unrestricted free agent in March and is coming off his best professional season.

The tag period for the 2014 offseason begins Monday and runs through March 3. Thompson hasn't been quick to use the tag in the past, and he's not likely to use it now, even though the situation revolving Shields appears to be one made for the designation.

He fits most of the criteria.

Shields is a young, ascending player who is valuable to the Packers. Given his refusal to sign a new long-term deal last spring and the inability of the two sides to come to a deal by now, Shields might also prove difficult to lock up before the start of free agency on March 11. Slapping on the tag gives Green Bay another year to work with and provides Shields the necessary incentive to ink a long-term deal this offseason.

However, Thompson's history of the tag and the price it would cost the Packers to use it on Shields makes it increasingly less likely that the cornerback will receive the tag.

Since becoming general manager of the Packers in 2005, Thompson has used the franchise tag twice and the transition tag—a form of designation that grants a team right of first refusal—only once. He put the franchise tag on Corey Williams in 2008 and on Ryan Pickett in 2010, and he put the transition tag on Bubba Franks in 2005.

Williams, an up-and-coming defensive tackle, was eventually traded to the Cleveland Browns for a second-round pick. Pickett voided his tag when he signed a new long-term deal. Franks never signed his transition tag but eventually agreed to a new seven-year deal to stay in Green Bay.

Thompson has been presented the opportunity to use the tag in previous seasons, including in 2012, when backup quarterback Matt Flynn entered free agency, and in 2013, when the contract of Greg Jennings was up and the Pro Bowl receiver looked likely to leave. He declined the opportunity each time.

It's now been four years since Thompson last used the franchise tag, and overall, he hasn't used the designation during seven of his nine years on the job.

He'll likely make it eight offseasons in 10 years by March 3, as the price to tag a player like Shields is probably too exorbitant for Thompson to handle.

Cornerbacks and the Franchise Tag, 2009-2013 Player Team Cost* 2009 Dunta Robinson HOU $10.0M 2010 None N/A $9.6M 2011 None N/A $13.5M 2012 Brent Grimes ATL $10.3M 2013 None N/A $10.9M *2014 cost expected to be $11.3M

Cornerbacks are expected to cost $11.3 million to franchise tag this offseason, up from $10.9 million in 2013. No player at the position received the tag last offseason. In fact, Brent Grimes in 2011 represents the only cornerback since 2010 to be franchise-tagged.

Teams simply don't want to pay the hefty one-year cost for a cornerback. It's a valuable position, but unless you're dealing with Darrelle Revis or Richard Sherman, there's no way to get sound value with the franchise tag.

Instead, teams like the Packers are more likely to allow a player like Shields to get to the open market and then gauge his value from there. The cornerback market in 2014 is not a historically talented pool by any means, but there are several starting-level players looking more and more likely to get to free agency. These include Alterraun Verner, Aqib Talib, Grimes, Brandon Browner, Walter Thurmond, Dominique Rodgers-Cromartie, Charles Tillman, Captain Munnerlyn, Tarell Brown and Vontae Davis.

Maybe the Packers fear that Shields is the cream of that crop and will command top cornerback money, but even in that scenario, he'll make far less per season than the $11.3 million required by the tag.

More likely, Shields will enter a crowded market and find it difficult to hit on the price currently being juggled around in conversations with the Packers.

It's more than telling that the Tennessee Titans are comfortable letting a player like Verner, a 2013 All-Pro, hit free agency without using the tag, per Jim Wyatt of The Tennessean. According to Pro Football Focus (subscription required), Verner, Grimes, Davis, Rodgers-Cromartie, Munnerlyn, Thurmond, Brown and Browner all graded out higher than Shields last season.

By tagging Shields, the Packers would lose some of the negotiating leverage that comes with market supply and demand. It would give agent Drew Rosenhaus a clear indication that Green Bay values Shields at or somewhere near $11.3 million, which is almost $3 million more than the Packers were willing to pay Tramon Williams with his last deal.

The tag also traps Thompson and the Packers into a non-voidable $11.3 million cap hit if Shields signs the franchise tender and the two sides are unable to agree on a new deal. Green Bay has plenty of cap room—around $28 million with rollover money from 2013—but allocating so much of that cap to one player would rob Thompson of much of his acquiring power this offseason. And the Packers have several other free agents to sign this spring, plus an incoming draft class that typically costs roughly $5 million.

There are compelling arguments for using the tag on Shields. He's a developing player with star potential; a cornerback who runs extremely well, makes plays and is still learning the position. The tag would provide another year of observation before spending big on a multi-year deal. The timeline works out, too, as veteran cornerback Tramon Williams comes off the books after 2014. By then, the Packers will have a better idea if Shields is the guy they want long term in Williams' price market.

Yet the arguments against using the tag are just as compelling and likely more rational, given Thompson's history with the tag and the hefty cash associated with the designation.

The Packers don't want to lose a player like Shields, but they also don't want to handcuff themselves financially. The only way to have both is to let Shields hit free agency, where a crowded market will likely provide better footing for a more palatable long-term deal.