Giannis Antetokounmpo's supermax decision with the Milwaukee Bucks looms over the NBA

The compressed NBA offseason has been as frantic as predicted. But the only thing that might truly matter has yet to be settled: whether Giannis Antetokounmpo signs his five-year, $228 million supermax extension in the coming days.

It's as big a moment as the league has had since Kevin Durant's free-agency move to Golden State in 2016.

There have been numerous superstars to relocate and change the balance of power in the league since then. But Antetokounmpo's choice not only defines the future of the Milwaukee Bucks, it controls how a handful of franchises, some with championship aspirations, handle their strategy for the next year. And perhaps the fate of the supermax contract itself.

Antetokounmpo's signing, whether now or next summer, is likely the most important moment in the Bucks' franchise history since Kareem Abdul-Jabbar asked to be traded in 1974. Milwaukee hasn't had a player this good since -- and hasn't been back to the Finals either.

Internally, league sources said, the Bucks have gone from cautiously optimistic to cautiously confident in recent weeks that the outcome will be favorable when Antetokounmpo returns from Greece, where he has been since mid-September.

The moves they've made telegraph their confidence. They didn't trade three first-round picks and two pick swaps for Jrue Holiday without insight. There's no question Milwaukee felt the need to make roster upgrades, especially in the backcourt, after last season's playoff disappointment. That is part of a case being made to the reigning two-time MVP. But the Bucks were also acting with confidence that they weren't mortgaging a future without Antetokounmpo. They hope.

At the same time, there are teams clearly hedging that Antetokounmpo will not extend his deal before the Dec. 21 deadline. It shows in their free-agency moves.

The Miami Heat signed four players, all of them with just one-year guaranteed deals to protect 2021 cap space. Their young star, Bam Adebayo, is the only expected max-extension-worthy player from the 2017 draft class yet to get a deal as the Heat wait to determine how to proceed.

The Dallas Mavericks made a flurry of moves, but by moving off the guaranteed contracts of Delon Wright and Seth Curry and adding Josh Richardson -- likely to opt out next year -- they've kept a slot open for Antetokounmpo. The Toronto Raptors and New York Knicks, wherever they might realistically be on a hypothetical list, have taken steps to keep their caps clean as well.

And there are more teams lurking, many more. For more than a year, teams have been building dossiers, from the role of the closest people in his life -- his longtime girlfriend and his brothers -- to his admiration for international players who have come over to become successful like him. That and other intel has been collected to use if an opportunity arises.

As a reminder, Antetokounmpo stands to guarantee himself an additional $83 million by taking the Bucks' supermax now rather than leaving in free agency next year. It's a fact meant to render free-agency uncertainty moot, which is why owners added it into the rules after Durant left the Thunder.

Basic game theory would suggest Antetokounmpo's best move would be to take the money now and worry about his long-term tenure in Milwaukee later. The Bucks would never say this publicly, but such a risk is one they'd probably accept at this point in time vs. playing the upcoming season with future uncertainty hanging over the team.

Currently there are three players on supermax contracts who have reportedly asked to be traded: James Harden, Russell Westbrook and John Wall. Westbrook, of course, for the second time on his supermax.

But there's also Kawhi Leonard and Anthony Davis, players who rejected the supermax offer and demanded to be traded. Paul George also asked out with the supermax as a possibility (he didn't end up qualifying for it). This vital aspect of the collective bargaining agreement has a spotty record, and, if Antetokounmpo doesn't use this path, it's fair to wonder whether it will exist at all in the future.

Antetokounmpo's case stands unique from these, at least for now. If he doesn't extend, he likely won't be traded.

All of which only raises the stakes even more as the league watches, ready to pounce. And the Bucks wait, too, ready to celebrate the closest thing to a championship any team in this era can.

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