Jaylen Brown is coming off a legacy-defining season.

The eight-year NBA veteran made his third All-Star team, then won Eastern Conference finals MVP and Finals MVP while helping lead the Boston Celtics to their first NBA championship since 2008. It's the kind of effort that places him in the pantheon of Celtics lore and squashes criticism of his $304 million contract extension that made him the highest-paid player in league history when he signed it.

What it didn't do is land him a spot on Team USA for the Paris Olympics. Brown missed the initial cut for the final roster that's gathered in Las Vegas this week for training camp. When Kawhi Leonard withdrew on Wednesday — opening up a roster spot — Brown missed out again.

Team USA instead selected Brown's Celtics teammate Derrick White to replace Leonard. Here's how Brown responded on social media when that news broke:

Brown followed up with another tweet insinuating that Nike — which outfits Team USA — had something to do with him being left off the team.

Brown is a sneaker free agent, but had a contract with Adidas through 2021. He also has previous beef with Nike dating back to founder Phil Knight's 2022 criticism of his friend Kyrie Irving when Irving was suspended by the NBA.

Team USA responds

USA Basketball managing director Grant Hill denied Wednesday night that Nike has anything to do with any roster decisions.

"For a good portion of my career, I wore FILA" Hill said, with a laugh. ... "We're proud of our partners, obviously, at USA Basketball. But this is about putting together a team. ...

"You've got 12 spots. You have to build a team. One of the hardest things is leaving people off the roster that I'm a fan of, that I look forward to watching. ... The responsibility that I have is to put together a team and a team that complements each other, a team that fits, a team that will give us the best opportunity for success. Whatever theories that might be out there, they're just that."

Will this spill over in Boston?

Cryptic social media activity is a hallmark of the modern professional athlete experience, and Brown's tweet is a prime example.

Ambiguous emoji use ranks alongside stripping social media of team references during contract disputes as a sign of displeasure. Such ambiguity delivers a message while leaving an out.

In this case, the ambiguity allows him to voice his displeasure without directly criticizing the selection of his teammate to the Olympics roster. Though it's not as if White and everyone else in Boston is incapable of doing the math here. And it's not like Brown's not aware of that.

Brown's certainly earned serious consideration for an Olympic roster spot; being disappointed to not secure one is a natural reaction. Lobbing conspiracy theories is another issue altogether.

Why did Team USA select Derrick White?

As Hill explained, roster building for the Olympics is not like selecting an All-Star team or an All-NBA team. Beyond the very top of the roster, it becomes about fit and building a team to compete against the rest of the world's best — rather than simply selecting the 12 best available players.

In this instance, Team USA lost an elite defender in Leonard — a seven-time NBA All-Defensive team selection and a two-time Defensive Player of the Year. In selecting White, it added another elite perimeter defender and an outstanding two-way player.

White earned All-Defensive team honors for a second consecutive season while averaging one steal and 1.2 blocks per game as a guard. He's able to stifle an opponent's best perimeter player, challenge shots at the rim and confidently knock down 3-pointers (39.6% on 6.8 attempts per game last season) on the other side of the court.

It's a valuable skill set that likewise played a significant role in Boston securing the NBA championship this season. It's understandable why Team USA made him a priority.

It's also understandable that Brown would be upset.