Cops arrest man after football freshman is hospitalized by shuddering one-punch knockout in street fight over ‘mom’ insult (VIDEO)

Police say they have arrested a man after a footballer hit his head on the pavement when he copped a knockout blow during a street fight in the US, with footage appearing to show him accusing his assailant of insulting his mother.

Wide receiver Carnell Davis, who plays for Rutgers University's Scarlet Knights, squared up to a man confirmed by police to be Alexander Denafo in a lightning scrap that was caught on camera, widely shared and said to have started during a football game on a beach in New Jersey.

Half-naked Davis appears to confront Denafo while accusing him of saying he would "f*ck my mom", receiving a push in his chest that sends him backwards before both men raise their fists and size each other up.

Denafo then lands with a huge first shot, thumping Davis in the head before he collapses to the road while a person outside of the shot can be heard expressing their horror at the shocking set-to.

“Both men mutually decided to leave the beach to continue the altercation, which developed into a physical fight,” the Margate Police Department initially revealed in a statement.

They added after the arrest: “Cell phone video obtained of the incident revealed Denafo struck Davis in the face which caused him to fall to the ground and strike his head on the pavement."

Denafo is said to have been given a court date of July 26. “Our main concern is Carnell’s health and well-being,” the Rutgers said in their response to the fight. “We look forward to getting him back on campus soon.”

Viewers were understandably shocked by the violence. "Carnell Davis did not have a great 4th of July," said one account that shared the clip.

"Carnell is recovering. Please don’t get into fights anywhere, especially on the street.

"Anybody can get slept. Hit your head the wrong way on the pavement? That could be it."

Another ruefully advised Davis: "Got to move your feet. Shake my head."