NBA experienced several fan-related incidents in the last few days as the teams increase their stadium capacity after one and half season of playing in front of empty stands.

Portland Trail Blazers superstar Damian Lillard reacted to the latest incident that involved Kyrie Irving and one Celtics’ fan, who threw a bottle to the Nets’ superstar.

The implication from Lillard is a player-fan physical altercation will come if nothing is done to address the fan behavior. Four different fan-related incidents took place in the first week of the NBA playoffs.

A Knicks fan spit on Hawks guard Trae Young during Game 1 between Knicks and Hawks, a Sixers fan threw popcorn on Wizards guard Russell Westbrook, and three Jazz fans were banned from the arena for racist insults towards the family of Grizzlies guard Ja Morant.