The Knicks released a statement Thursday afternoon.
"We investigated the matter and determined that this patron, who is not a season ticket holder, did indeed spit on Trae Young, and for that reason, he is now banned from The Garden indefinitely. We apologize to Trae and the entire Atlanta Hawks organization for this fan's behavior. This was completely unacceptable and will not be tolerated in our venue. We have turned the information over to the appropriate authorities," the team said.
Young, however, has declined to press charges against the fan.
"We appreciate the Garden's response to the incident, and Trae's focus remains on his teammates and Game 3," Young's agent, Omar Wilkes, said.
This was the second fan-related incident to happen Wednesday; a fan in Philadelphia threw popcorn on Washington Wizards guard Russell Westbrook as he was heading down the tunnel. Philadelphia announced the punishment in that incident Thursday, as that fan was also banned indefinitely from the Wells Fargo Center.
The incident directed at Young occurred with 8:34 left in the fourth quarter while he was inbounding the ball on the sideline nearest to the fans. Video was widely circulated on social media.
Young has been the center of attention for Knicks fans, some of whom have chanted "F--- Trae Young" throughout the first two games.
Early Thursday, Young's father, Ray Young,tweeted: "Gotta get this under control. @russwest44 gets popcorn thrown on him & @TheTraeYoung gets spat on. I can deal with all the chants about my son, it comes with it. But this needs to be addressed." Trae Young also had retweeted the video, writing "Damn... Crazy !"
The NBA released a statement Thursday about the league's code of conduct in the playoffs being enforced: "The return of more NBA fans to our arenas has brought great excitement and energy to the start of the playoffs, but it is critical that we all show respect for players, officials and our fellow fans. An enhanced fan code of conduct will be vigorously enforced in order to ensure a safe and respectful environment for all involved."
The National Basketball Players Association also released a statement calling on fans to "Respect our Players. Respect our Game."
"True fans of this game honor and respect the dignity of our players," the statement read. "No true fan would seek to harm them or violate their personal space. Those who do have no place in our arenas. And their conduct is appropriately evaluated by law enforcement just as if it occurred on a public street."
Hawks interim coach Nate McMillan said he wasn't aware of the incident until Thursday morning but reiterated that "there is no place for that" in the game.
"You have to draw a line," McMillan said. "Unfortunately, I just think we're living in a society where really, people just don't have respect anymore. In no way should that be allowed or should that happen at a sporting event or really any event where you are coming to watch a game. I think New York did what they should've done in that situation. It's uncalled for. And it shouldn't happen."
Young did not speak at the Hawks' shootaround on Thursday afternoon, but his teammates who did speak let their feelings on the situation be known quite clearly.
"What happened with Trae or what happened with Russell Westbrook, you know, fans are passionate, but there's no place for any of that," Hawks guard Kevin Huerter said. "The response by the Knicks for banning him, I hope that lasts a long time if not forever.
"There's no place for it. These fans, if you take away the barriers and you take away security, if you're face-to-face with an NBA player and you think you're going to do something like that, I doubt it's gonna go your way. People gotta remember that."
Atlanta forward John Collins, who said he got into fights over people spitting during basketball games in his childhood, acknowledged that he doesn't know what else the NBA could do in those situations but still feels it's "unacceptable" behavior.
"I don't even understand, like, you're coming to a basketball game to watch a person play basketball, where does it come into your mind to spit at this person? How disrespectful," Collins said.
On Sunday, Young said he understands the history of players going into Madison Square Garden and being painted as villains by Knicks fans.
"Like I said, I take that as a compliment, to be honest with you," Young said following the Hawks' Game 1 win. "Obviously, I'm doing something right if you hate me that much. I embrace it and try to focus on my team and trying to help my team win. At the end of the day, we'll get the last laugh if we do that."
The Knicks and Hawks will meet in Atlanta for Game 3 on Friday. The series is tied at one game apiece.
ESPN's Malika Andrews contributed to this report.