NEW YORK — A sucker punch from a rival fan knocked one Lightning fan unconscious and landed a Rangers fan in handcuffs.

Not long after a brawl ensued among players at the end of Game 5 between the Tampa Bay Lightning and New York Rangers at Madison Square Garden, video captured the violent encounter outside the arena.

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The punch happened around 11:30 p.m. Thursday, according to the New York Police Department. The agency says there was "an interaction" between the two men prior to the Rangers fan, who police identified as 29-year-old James Anastasio, punching the Lightning fan in the face.

The punch caused the Lightning fan to fall to the floor unconscious, police said. 

As Anastasio tried to run away, police say the witness tried to stop him, which resulted in Anastasio punching the witness in the face, too. Officers say the witness "sustained pain and bruising" to his face, but he refused medical treatment.

Shortly after that, police say officers arrived and arrested Anastasio. He was charged with assault, disorderly conduct and harassment — each count twice for each person who was allegedly assaulted.

The man who was knocked unconscious is considered to be "stable," NYPD said.

What the crowd witnessed

Several Rangers fans are seen in the video stopping to help the Lightning fan laying on the ground, including Corey Brill, who said he hung around until close to midnight to make sure the man was okay and give a statement to police.

"It happened quickly, I saw the guy in red turn around and sucker-punch him," Brill said.

Brill said a nurse also stopped and put the man on his side and took his pulse, but it was about two to three minutes before the Lightning fan came back to consciousness.

When he came to, Brill said he was disoriented and thought he had fallen.

"I was like, 'I don’t know you, I feel I need to tell you, you need to press charges, you were just assaulted,'" Brill said.

MSG reacts

In a statement, Madison Square Garden called the incident "an abhorrent assault."

"Last night, an abhorrent assault took place against a Tampa Bay fan at the conclusion of the game — followed by a second assault against an individual who bravely intervened.

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"First, we ensured the victims received appropriate medical care and have followed up to provide support from our guest services team. Equally important, we are cooperating fully with law enforcement as this is now a criminal matter. The assailant will also be banned from The Garden and all other MSG venues for life.

"All guests- no matter what team they support- should feel safe and respected in The Garden. This has and always will be our policy."

The Bolts beat the Rangers 3-1 in Game 5, taking a 3-2 lead in the Eastern Conference Final series. Both teams will be back Saturday in Tampa for Game 6 at Amalie Arena. 

If the Bolts pull out a win at home, they will advance to the Stanley Cup Finals for the third season in a row and will take on the Colorado Avalanche. 

Editor's note: This story has been updated frequently with varying information from the New York Police Department. The agency first said there was some argument between the two men, then said there was no "altercation," and now says there was an "interaction."

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