Jared Goff helped lift Lions t...

You need a good quarterback to win in the NFL. You have to pay a good quarterback market value to keep him around. It becomes a lot harder to win once you pay that quarterback market value.

That's the conundrum all NFL teams face. There is three decades of history that indicates your quarterback better not make more than 13% of the cap, unless he's Patrick Mahomes, if you want to win a Super Bowl.

Jared Goff signed a $212 million deal over four years Monday, with $170 million guaranteed. It's an awesome story: A player who was dumped by the Los Angeles Rams for something better becoming one of the highest paid players in NFL history. Goff was a supposed throw-in for the Matthew Stafford trade. He has been way more than that. He helped the Lions to their most successful offseason since 1957 and had fans chanting his name.

The issue is that Goff's mega-deal, which begins in 2025, will make it harder for the Lions to keep winning, if history is any guide.

Jared Goff got a massive contract

You'll hear the axiom that you need an elite quarterback to win big in the NFL. That's not completely accurate. It should read that you need an elite quarterback who isn't taking up too much of the team's salary cap.

From the start of the salary cap era in 1994 until Mahomes' second Super Bowl win, the magic number was 13.1%. Steve Young made 13.1% of the 1994 San Francisco 49ers' salary cap when they won the Super Bowl. Every single Super Bowl-winning quarterback after that, until Mahomes and the Kansas City Chiefs beat the Philadelphia Eagles two seasons ago, was under that 13.1% mark, according to OverTheCap and Spotrac.

It's easy to figure out: When one player is taking up that much of the salary cap, it's hard to build a championship team around him.

The specific details of Goff's deal weren't in as of Tuesday morning, but a deal worth $53 million per year is going to be well over 13.1% no matter how it is structured, when it kicks in after the 2024 season. The salary cap this year was $255.4 million and $53 million would be 20.8% of that. The cap would have to explode to get Goff close to that 13% range.

From 2011 through 2021, the median cap percentage for the winning Super Bowl quarterback was a touch over 10%, according to Spotrac. Goff could be double that for some of his extension, depending on how the cap increases.

Mahomes changed the narrative a bit. The past two seasons, Mahomes' cap hits were 17.2% and 16.5%. But Mahomes is an outlier in many ways. Even Lions fans who love Goff wouldn't proclaim that he's in Mahomes' class as a quarterback. Mahomes doesn't represent a new era for all quarterbacks; he's just an era unto himself.

It's not like the Lions had much choice. Goff helped Detroit to the NFC championship game and the Lions should feel like they're Super Bowl contenders for the next few years. They felt they had to pay him. But Goff's deal will make it harder to win.

Can Lions win big with Goff?

The caveat to Goff's deal is that if the Lions do win a Super Bowl nobody will care what he made. His statue outside of Ford Field wouldn't include his salary cap number.

While Goff's play was a big reason the Lions won a division title for the first time since 1993, doubled their number of playoff wins since 1957 and had a big lead in the second half of the NFC title game, he's far from the only reason. Detroit has a top five offensive line, an elite receiver in Amon-Ra St. Brown, two good running backs in David Montgomery and Jahmyr Gibbs and dynamic tight end Sam LaPorta coming off a huge rookie season. The infrastructure around Goff is tremendous. He has done his part, but outside of Michigan most rankings wouldn't have him as a top 10 quarterback. Soon (for now) he will be the second highest paid player in NFL history, in terms of average per year.

That will make it tough for the Lions to continue to maintain a great roster around Goff, which he probably needs to be as productive as he was last season. It'll be harder for Detroit to have depth on the offensive line or pick up a good third receiver or add pass rushing or secondary depth. That's just life in a salary cap league.

Maybe Detroit's situation will be different. The Lions have plenty of good, young players who don't need to be extended for at least a couple years. Their front office, led by general manager Brad Holmes, has been one of the best in the NFL the past few years and they'll get creative.

And while the structure of Goff's deal will matter for Detroit's flexibility around him, his extension isn't expected to kick in until 2025. Goff's salary cap number this year is 12.7%, according to Spotrac, a reasonable rate for a Super Bowl winning quarterback over the last 30 years. Maybe there should be some extra urgency in Detroit this season.