With big deal QB such as Joe Flacco and Matt Ryan flailing, are we approaching a salary bubble?

Tom Pelissero | USA TODAY Sports

The Baltimore Ravens didn't have much choice. Neither did the Atlanta Falcons.

It's too tough to find a starting quarterback to let one walk, even if the price tag rises beyond what was expected or what's palatable under the salary cap.

So, the Ravens gave Joe Flacco a six-year, $120.6 million contract. Less than five months later, Matt Ryan signed a six-year, $113.75 million deal with the Falcons.

"If you're going to ask for that much money, you know it's going to be difficult around there," an executive in personnel for another NFL team told USA TODAY Sports, speaking on condition of anonymity for competitive reasons. "What's Baltimore's record? What's Atlanta's record?"

The Ravens are 4-6. The Falcons fell to 2-9 with Thursday's home loss against New Orleans.

Quarterback play isn't solely to blame. Neither are the contracts of Flacco and Ryan, who count just $6.8 million and $9.6 million against the 2013 cap, respectively. The same goes for the Dallas Cowboys' 5-5 start after Tony Romo signed a seven-year, $119.5 million deal.

But here's the question: importance of the position aside, is there a point at which the bubble bursts even for good, solid quarterbacks who aren't elite players?

Flacco, 28, signed the largest contract in NFL history – topped less than two months later by Aaron Rodgers' seven-year, $130.75 million deal with the Green Bay Packers – in part because Rahim Moore misjudged one deep ball, launching the Ravens' championship run last year.

Ryan, 28, got even more guaranteed ($59 million to Flacco's $51 million) after showing growth in an offense that fell apart the moment his top two receivers got banged up.

Romo, 33, is now on his second true megadeal, this one including $55 million guaranteed, even though the Cowboys have exactly one playoff win in his eight seasons as the starter.

Will Jay Cutler see a similar windfall if he hits free agency, just for being an above-average starter when healthy? Will Ben Roethlisberger top $20 million a year on his next restructure?

What happens when the likes of Cam Newton, Andrew Luck and Russell Wilson decide to hold their teams over the coals once they're eligible for long-term deals in the next couple years?

"That's where sustainability becomes (bleeping) really tough," the executive said. "That's where you've got to draft well. If you miss out one or two years, you're screwed."

Flacco's cap number rises as high as $31.15 million in 2017. Romo's reaches $25.273 million. Ryan's goes to $23.75 million.

Drew Brees ($20 million a year), Peyton Manning ($19.2 million), Rodgers ($18.7 million) and Tom Brady ($11.4 million) are far more valuable, but their salaries don't reflect that.

Until you have a quarterback, you don't have anything, giving any viable starter leverage when it comes time to do their second (or third) deals. But the game changes once a sixth or more of a largely flat cap is devoted to one player who may not even be among the 10 best at his position.