LeBron James has labelled the mandate that continues to prevent Kyrie Irving from playing home games for the Brooklyn Nets as making "absolutely zero sense" after Irving was spotted in the crowd at Barclays Center on Sunday.

New York City mayor Eric Adams recently removed restrictions requiring proof of vaccination to enter establishments including bars, restaurants and sports arenas, but the mandate for private sector employees remains in place.

As a result, Irving – who is unvaccinated – is only able to attend home games as a spectator, which he did on Sunday as the Nets beat the New York Knicks 110-107, with reports suggesting he was expected to be a presence in the locker room as well.

The 29-year-old was also in attendance at Barclays on Saturday to take in Duke against Virginia Tech.

Los Angeles Lakers star James took to Twitter on Sunday to question the decision to allow someone who can be in the arena anyway to be on the court.

Quote tweeting a post asking that very question, James wrote: "FACTS FACTS FACTS!! It literally makes ABSOLUTELY ZERO SENSE!!! They say if common sense was common then we'd all have it. Ain't that the truth. #FreeKyrie".

Irving has played 18 games for the Nets this season, all on the road, averaging 25.9 points per game, and recently hit 50 in his team's win at the Charlotte Hornets.

The former Cleveland and Boston point guard said last week he believed Adams was on his side.

Adams said last week that allowing Irving to play home games "would send the wrong message" to the people of New York, despite wanting to see Irving win an NBA championship, thus ruling out an exemption.

"Shoutout Eric Adams, man," Irving told reporters after the Nets' loss to the Celtics last Sunday.

"It's not an easy job to be the mayor of New York City. And with COVID looming, the vaccination mandates, everything going on in our world, with this war in the Ukraine, and everybody feeling it across America, I wouldn't want to be in his shoes right now trying to delegate whether or not one basketball player can come and play at home.

"I appreciate his comments and his stance. He knows where I stand, and I know one day we'll be able to break bread together and he'll be able to come to the games and hopefully we'll move past this time like it never happened in one sense.

"But, it's just the reality that it's been difficult on a lot of us in New York City and across the world. So, I know he's feeling it and I'm just grateful that he's on my side, as well as the [NBA] commissioner."