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Editor's Note: Since publish, the Eagles have decided not to use the franchise tag on Nick Foles. He will be an unrestricted free agent in March.

As Nick Foles led the Philadelphia Eagles on a Super Bowl run in 2017 and then a playoff run in 2018, the natural assumption was that the signal-caller was making himself a very rich man.

After all, Foles plays quarterback in a quarterback-centric era within a quarterback-obsessed league. He should be in his prime based on his age (he just turned 30), and we know NFL teams drool over perceived winners. Foles won 10 of his 13 starts for the Eagles the last two years, including four in the playoffs, and he's one of just six active quarterbacks with the words "Super Bowl MVP" on his resume.

But the market for Foles might not be as grand as many of us figured when Foles was working his magic back in December and January. Here's why.

The quarterback supply and demand dynamics aren't what they once were

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When Foles essentially bought his freedom by paying $2 million to void a $20 million option in his contract for 2019, he was gambling on his prospects as a free agent.

The Eagles could still slap him with the franchise tag for roughly $25 million in hopes of flipping him to a team in need of a starting quarterback, but that would be an even larger risk because there are so few teams that would be surefire suitors for an expensive veteran quarterback.

That's especially the case now that, according to ESPN's Adam Schefter, the Denver Broncos have a trade agreement in place for veteran Joe Flacco, who will fill a potential vacancy without opening up a new one because 2018 first-round pick Lamar Jackson has already moved into a starting role with Flacco's former team, the Baltimore Ravens.

For years we've been able to confidently state that the NFL contains 32 franchises but far fewer than 32 franchise-caliber quarterbacks, but that might no longer be the case. Not only do the Broncos and Ravens almost certainly feel they have starting quarterbacks in place, but so does every other team except maybe the Jacksonville Jaguars, Miami Dolphins, Washington Redskins and New York Giants.

The problem is Spotrac projects that the Jaguars will have less salary-cap space than every other team in the league when free agency opens, which could make it hard to break the bank for Foles.

The Dolphins are also one of just seven teams projected to possess less than $12 million in cap room, and there are strong indications they're rebuilding.

Meanwhile, since they share a division with the Eagles, the Redskins and Giants might be off the table for a potential tag-and-trade scenario. Plus, Washington is already paying the injured Alex Smith more than $20 million and is low on cap space, while the Giants owe Eli Manning more than $23 million.

Young quarterbacks are all the rage right now

The Giants, Redskins and Dolphins have more wiggle room to find money for Foles, but those three are also more likely than Jacksonville to go the draft route in search of their next franchise quarterback. That's because they're all either rebuilding or already committed to an expensive veteran quarterback. In fact, both of those trends apply to the Dolphins, who also still have Ryan Tannehill on the payroll.

This draft class isn't loaded with highly touted quarterbacks, but the recent addition of Oklahoma Heisman Trophy winner Kyler Murray gives more weight to a group that also includes first-round-worthy Ohio State product Dwayne Haskins as well as potential first-rounders Drew Lock and Daniel Jones out of Missouri and Duke, respectively.

The worst-case scenario for Foles involves the Giants, Jags, Dolphins and Redskins all using top-15 picks on those passers, but it would also be problematic if three of them decided to go the draft route at quarterback. It'd be hard to get a bidding war going when you have a market of one, and that could easily end up being the case.

And it's not unrealistic. A big reason the franchise-caliber quarterback supply has increased (and in turn caused the demand to decrease) is that there's a new wave of talented young quarterbacks taking the league by storm.

The 2018 draft alone gave a handful of teams supposed franchise quarterbacks in Baker Mayfield (Cleveland Browns), Sam Darnold (New York Jets), Josh Allen (Buffalo Bills), Josh Rosen (Arizona Cardinals) and Jackson (Baltimore), while the 2017 draft gave the Chicago Bears Mitchell Trubisky, the Kansas City Chiefs Patrick Mahomes and the Houston Texans Deshaun Watson.

In other words, a quarter of the league's current starting quarterbacks were drafted in the last 22 months, and most of them are off to promising starts.

Throw in Jared Goff, Carson Wentz and Dak Prescott from the 2016 draft, and it's easy to understand why teams might prefer to give the draft a shot right now. The NCAA has been sending the NFL some high-quality passers of late, which could make it harder for someone like Foles to strike open-market gold.

The Kirk Cousins Effect?

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It's also possible that a quarterback-needy team without a lot of competition on the free-agent/trade market decides it might be better off saving money and pursuing Tannehill, Blake Bortles, Case Keenum, Teddy Bridgewater or Ryan Fitzpatrick, all of whom could be available.

Because while Foles has a higher ceiling than all of the above, there might still be some trepidation about bringing in a high-priced quarterback on the wrong side of 30. That's what the Minnesota Vikings did with Kirk Cousins a year ago, and that buzzworthy $84 million signing did not immediately pay off. In his first year with the Vikes, Cousins ranked in the bottom 10 among qualified passers with a 7.1 yards-per-attempt average and struggled mightily in big games, and Minnesota missed the playoffs.

Drafting quarterbacks is vogue, while signing experienced quarterbacks to bloated contracts might be going out of style fast. Not only did Cousins fail to live up to his fully guaranteed salary in 2018, but based on numbers from Spotrac, each of the NFL's five highest-paid quarterbacks failed to get their respective squads to the playoffs this past season.

Is Foles that good?

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And then there's the fact that Foles hasn't been consistently productive for an extended stretch at any point in his career. Is he another Cousins? Is that the best-case scenario? Could he be another Keenum?

That Super Bowl run was astonishing, and Foles also deserves credit for steering the ship as Philadelphia made another improbable late-season run in 2018. He also posted the third-highest qualified single-season passer rating in league history during a remarkable but seemingly aberrational 2013 campaign.

But Foles' passer rating since returning to the Eagles in 2017 is only 90.3 thanks to a concerning 6.6 yards-per-attempt average. That doesn't include last year's playoff performances against New England Patriots, Vikings and Atlanta Falcons, but it's also worth noting that he struggled mightily at times this past postseason. Foles threw more interceptions (four) than touchdown passes (three) while posting an ugly 70.6 rating in two 2018 playoff games, and he and his team undoubtedly benefited from good fortune in a Wild Card Round victory over the Bears.

It often seems as though Foles has been favored by the football gods, and it's possible teams will be excited to pay top dollar for some of that magic dust. But business decisions are rarely made based on intangibles, and the reality is Nick Foles isn't a special quarterback on paper.

With that in mind under the current circumstances, he could have more trouble than expected finding a pot of gold in March.

Brad Gagnon has covered the NFL for Bleacher Report since 2012.