Madison Square Garden said it had banned a New York Rangers fan for life.
After being seen hitting a Tampa Bay Lightning fan in the face on Thursday after the fifth game.
According to a video posted on social media, the Rangers fan turned around and struck the Lightning fan.
knocking the men to the ground as they competed after a 3-1 victory over Tampa Bay.
The killer apparently left the area while other people helped the attacker.
Friday's Madison Square Garden statement called the incident a "disgusting attack,"
Saying a Rangers fan attacked another man who tried to strike.
"We are fully cooperating with law enforcement agencies because it is already a criminal matter.
The killer will also ban The Garden and all other sites of MSG for life,
"MSG said in a statement. All visitors - no matter what team they support - should feel safe and respected at The Garden.
This is our policy and always will be. "
Police in several places confirmed that a 29-year-old man from Staten Island had been arrested in two cases of assault,
There was an interaction between the Rangers and Lightning fans before the punch struck, police said.