The Brooklyn Nets' long-awaited return to the Barclays Center was not enough to drive them to win over the Charlotte Hornets, as they fell 119-110.
After New York City's restriction on unvaccinated artists and athletes was repealed, he was finally able to perform.
The 30-year-old had 16 points, two rebounds, and 11 assists in the game.
LaMelo Ball stole the show for the Hornets, leading the team in scoring with 33 points.
Irving's teammate Kevin Durant questioned New York's Covid-19 restrictions earlier this month, which permitted players without the Covid-19 vaccine to watch but not participate in games.
Charlotte has won seven of their last eight games, while they have lost two of their last three.
Elsewhere, despite LeBron James' 39-point haul in just 42 minutes, including nine rebounds, the LA Lakers were beaten 116-108 by the New Orleans Pelicans.
James tweaked his ankle in the second quarter, as the Lakers blew a 60-40 lead, making him a doubt to face the Dallas Mavericks on Tuesday.
The Mavericks head into that clash off the back of a 114-100 victory over the Utah Jazz, with Luka Doncic scoring 32 points, Reggie Bullock 23 points and Jalen Brunson 22.
