What we know about Drew Brees is that he will play for the New Orleans Saints in 2018. Yes, the final three years of his contract will automatically void on March 14, which would make him an unrestricted free agent and the hottest commodity on the market.

But Brees has said repeatedly that he has no interest in leaving New Orleans, the Saints are poised to enter 2018 as one of the favorites in the NFC and there’s no reason to think the quarterback has any interest in testing the market. He’s certain to be a Saint for 2018 and probably for life.

What we don’t know about Brees is how he and the Saints will get his contract to where it needs to be for this to happen. They can’t simply do nothing. If they do nothing, those final three contract years void at the start of the new league year on March 14, and the Saints will be stuck with $18 million worth of signing bonus prorated on this year’s salary cap in addition to whatever salary they end up paying Brees for 2018. This would be a crusher, and New Orleans can’t let it happen, which is why March 14 is a very real deadline for Brees and the Saints to come to agreement on some kind of new contract.

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What will that contract look like? Well, that’s another thing we don’t know. To this point, Brees and the Saints have not had any serious discussions about it, which is probably because the Saints don’t fear him leaving. But at some point in the next month, they must. So here are some questions and answers about the Brees situation and where it’s headed:

What was that you said before about $18 million?

Yeah, this is NFL salary-cap math. Prior to the 2016 season, the Saints and Brees did a new contract that was technically a five-year deal even though it was really only a two-year deal. That deal included a $30 million signing bonus, and NFL rules allow teams to prorate signing bonus money over the life of the deal, up to five years. So, since 30 divided by five is six, the Saints have to count only $6 million of Brees’ signing bonus each year of the “five-year deal.” But the 2018, 2019 and 2020 seasons are just “dummy” years, added onto the contract solely for the purpose of salary-cap proration.

If nothing is done to the contract, all three of those years automatically void on March 14, and by rule, all of the remaining $18 million of salary-cap proration would accelerate onto this year’s cap. Once again, the Saints would be stuck with that charge before they even signed Brees. So if they signed him for, say, one year and $28 million, his salary-cap charge this year would be $46 million, which obviously would be way too much.

OK, so can’t they just agree that this year won’t void, and keep the contract as is otherwise?

Sure, they could. If they did that, Brees would be scheduled to earn a $22 million salary this year, and the cap charge would be $28 million ($22 million salary plus $6 million of the signing bonus). The Saints could carry that, for sure, and just delay this decision by a year. The problem is, Brees would have to agree to that alteration, and he wouldn’t be getting anything out of it. Even as his insistence that he doesn’t want to go anywhere hurts his negotiation leverage, that March 14 deadline creates some. The Saints don’t want to get hit with that $18 million cap charge.

Drew Brees has missed only three games since 2004, when he was with the Chargers. Photo by Stephen Lew/Icon Sportswire

So, what would Brees want to get out of this?

This is all hypothetical, because the team and player haven’t had discussions on a new deal yet, but play along with me here. Let’s say for the sake of argument that Brees wants to establish a new quarterback contract standard. He became the first $20 million-per-year player when he did his deal with the Saints in 2012, so let’s just say for the sake of argument that this time around he’d like to be able to say he was the first $30 million-per-year player. Brees and the Saints could do a new five-year contract that runs from 2018 to 2022 and includes four voidable years. Hypothetically, let’s say he gets a $29 million signing bonus and a $1 million 2018 salary. The Saints could spread the signing bonus out over five years for cap purposes and Brees could claim to be the first $30 million quarterback.

In the short term, this wouldn’t be a terrible thing for the Saints. If you could get a theoretical $1 million salary, plus $5.8 million worth of the $29 million signing bonus, plus the $6 million signing bonus proration left over from the current deal, Brees’ 2018 cap number would be $12.8 million. That would actually be significantly less than the $19 million he cost the Saints against the cap in 2017, and would enable them to sign free agents or do new contracts for other players on the roster. Sounds like a win-win, especially since the Saints start out the offseason in decent cap shape with about $25 million in cap room now.

The long-term problem for the Saints on a deal like this is that they could end up stuck with cap costs in the range of $22 million to $24 million in 2020 and beyond for a player who no longer plays for them because he’s retired. Brees is 39, after all, and isn’t likely to see the end of a five-year deal. And even if he does play only one more year and decides he wants to play again in 2019, the Saints in this hypothetical scenario would find themselves in the same situation a year from now, only $30 million poorer.

Could the Saints just franchise him?

No, they can’t. First of all, the contract to which Brees agreed in 2016 contains a provision specifically prohibiting the team from using the franchise tag on him. And even if it didn’t, the fact that the voiding deadline is after the March 6 franchise tag deadline means they couldn’t franchise him anyway. And even if they could, Brees’ franchise tag would be about $29 million (120 percent of his 2017 salary), which combined with the $18 million salary-cap proration would create an untenable number. Brees cannot be franchised.

Can’t Brees just do what Tom Brady does, and give the team a discount?

Well, he could, but it seems unlikely. Brees has been a prominent voice in the NFLPA as a one-time member of the union’s executive committee, and as such he’s not likely to do a deal that doesn’t help drive the market forward.

Further, Brees’ agent is Tom Condon, who represents a number of high-level quarterbacks and likely won’t want to do a deal that fails to move the market forward. Condon last year did Matthew Stafford’s extension with Detroit, a deal that set new quarterback benchmarks such as a $27 million annual average (since surpassed by San Francisco’s Jimmy Garoppolo) and $60 million in guaranteed money at signing.

Drew Brees set the NFL record for completion percentage (72.0) in 2017. Mark Konezny/USA TODAY Sports

Another Condon client, Atlanta’s Matt Ryan, will be in the market for an extension this summer. Brees’ and Condon’s history strongly suggests that any new Brees deal will be one that helps -- and not hurts -- Ryan’s chances of sailing past Stafford and Garoppolo and Kirk Cousins and Aaron Rodgers and any other top quarterback who does a new contract anytime soon. The odds of Brees “pulling a Brady” and giving the Saints a break just because he wants to stay there seem relatively low.

So, how does it all work out?

There has to be a compromise somewhere between the Saints’ likely preference of simply activating the 2018 portion of the current contract and Brees’ likely preference of another five-year dummy deal with massive up-front money. Maybe that means a shorter-term contract than the five-year deal he signed two years ago. Maybe it means signing him for two or three “real” years and betting he’ll play until he’s 41, which is possible.

Somewhere between the $22 million scheduled on the current dummy deal and that $30 million new-benchmark figure is probably the right number for Brees to be making in 2018. He and the Saints might need the next month to figure out what that number is, but odds are they’ll get there.

Insisting on a brilliant new record might be the way Brees would prefer to go, but it also could cost him a chance to meet his stated goal of staying in New Orleans. There’s room to get a new deal done, but there’s also a deadline by which the Saints need to do it. Both sides are motivated, and they’ll find a way, as they always have before.