NEW YORK -- The NBA fined the Brooklyn Nets $50,000 on Monday for letting Kyrie Irving into their locker room during a game in which he was unable to play because he is not vaccinated against COVID-19.

Irving was a spectator at Barclays Center on Sunday, sitting across from the Nets bench for Brooklyn's 110-107 victory over the New York Knicks. There is no longer a mandate that fans be vaccinated to enter the arena, but there is still one requiring it for someone who works there.

So the star guard had a seat in the stands, just as he did a night earlier to watch the ACC Tournament championship game. After the Nets game ended, he walked off arm-in-arm with Durant, who had scored a season-high 53 points, toward the locker room.

The league said in a statement Monday that the Nets violated New York City law and league health and safety protocols by permitting Irving to come into the locker room. Unlike the stands, the locker room is considered part of the team's workplace environment.

Durant spent a good chunk of his postgame interview calling on New York City Mayor Eric Adams to change the mandate, calling it "ridiculous" that unvaccinated people could be in the arena but not play in it. Coach Steve Nash acknowledged during his postgame availability that Irving had been in the locker room at halftime.

The Nets released a statement from Durant on Monday in which he explained the criticism he directed a day earlier at Adams, who took office in January.

"The last two years have been a difficult and painful time for New Yorkers, as well as a very confusing time with the changing landscape of the rules and mandates," Durant said. "I do appreciate the task the Mayor has in front of him with all the city has been through. My frustration with the situation doesn't change the fact that I will always be committed to helping the communities and cities I live in, and play in."

Until this week, proof of vaccination was required for fans. Though that mandate has been lifted, there is still one in place for those working at the arena. The Nets were already aggravated because that didn't apply to visitors, allowing an unvaccinated opponent to play when Irving couldn't. They seemed even more frustrated on Sunday, when Irving's arrival created a scene at a nationally televised game.