Should Miami match Brooklyn's big offer to Tyler Johnson?

— -- While they're busy pitching Kevin Durant and trying to re-sign Dwyane Wade and Hassan Whiteside, the Miami Heat now face another challenge.

On Sunday, the Brooklyn Nets reportedly offered Miami restricted free agent Tyler Johnson a four-year offer sheet worth $50 million. When Johnson officially signs the offer sheet after the NBA's moratorium concludes on Thursday, the Heat will have three days to decide whether to match.

Miami's decision is complicated by the back-loaded nature of the offer sheet, similar to the ones the Houston Rockets used to sign Jeremy Lin and Omer Asik in the summer of 2012.

Is Johnson worth the money? Or should the Heat let him leave?

Explaining the Arenas Provision

Because Johnson signed a two-year contract with Miami as an undrafted rookie in 2014-15, he was subject to a special provision of the CBA, informally named after former All-Star Gilbert Arenas because it closes the loophole that allowed Arenas to leave the Golden State Warriors for the Washington Wizards more than a decade ago.

Since the Heat don't have full Bird rights for Johnson, the biggest offer they can match to him without using cap space is the non-taxpayer midlevel exception. The Arenas provision limits offers to players like Johnson to that midlevel salary ($5.6 million) in Year 1, with a typical 4.5 percent raise in Year 2.

But in Years 3 and 4, the Nets were free to offer him up to his maximum salary. Brooklyn didn't quite get there -- a max "Arenas" offer would be for about $61 million over four years -- but Johnson's salary will jump to nearly $19 million in 2018-19 and $19.6 million in 2019-20.

While Johnson gets paid the same whether Miami matches or not, his cap hit is different. The Heat would account for Johnson's actual salary on their cap, whereas for the Nets, he counts at his average salary ($12.5 million) all four years.

That makes this contract tough for Miami. Johnson's huge raise would affect their flexibility in the last two seasons of his contract, and even if the Heat have already used cap space to build their core the next two summers, Johnson's salary could result in a huge tax bill for Micky Arison.

Johnson is just the third player to get a back-loaded offer using the Arenas provision, joining Asik and Lin. Asik's and Lin's former teams (the Chicago Bulls and New York Knicks, respectively) opted not to match those offers, so we've never seen a team deal with the cap implications of matching such a contract.

Projecting Johnson

So why is Johnson getting offered $50 million over four years just two years after going undrafted out of Fresno State?

At a listed 6-foot-4, Johnson is big enough to hold his own defending shooting guards but athletic enough to match up with point guards as well. According to Nylon Calculus' tracking, Johnson split his minutes almost equally between the two positions last season.

I don't think Johnson is a good enough playmaker to handle the point full-time, having handed out 3.3 assists per 36 minutes last season. But I like the idea of having him play both guard spots with the Nets, backing up and playing alongside new starter Lin.

A $50 million deal is about the most I would have been willing to offer Johnson (and precisely what I did as the Philadelphia 76ers' GM in the Dunc'd On mock offseason podcast). His multiyear projection values him at $28 million over the next three years, so this could be an overpay.

Still, Johnson is the kind of free agent Brooklyn is wise to target. At 24, this contract takes him through his prime, and it's not unreasonable to think Johnson might develop into a starter down the road. Given the Nets had about $34 million in cap space left -- and still have near-max money even with Johnson's salary on their books until or unless Miami matches -- this is a worthy gamble.

Why the Heat might match

So, given the unique challenges of the back-loaded Arenas offer, why is this a difficult decision for Miami? Because letting Johnson go doesn't create much additional cap space for the Heat this season, when he only counts $1.2 million against the cap before they officially match.

Because Miami must use cap space to re-sign Whiteside, the team's options for replacing departed starters Luol Deng and Joe Johnson are any remaining space after re-signing Wade, the $2.9 million room exception and players signed for the minimum salary.

It will be hard to find an equivalent talent to Johnson among those options, and after losing Deng and Joe Johnson, it's not clear the Heat can afford to let another rotation player walk away this summer.

So my expectation is that if they don't get a commitment from Durant after meeting with him, the Heat will conclude their use of cap space (including re-signing Wade) in time to match Brooklyn's offer.