Fans have reacted with disgust after disturbing vision showed a female fan leap to the defence of a man who was coward punched at an NFL match.
The shocking incident was captured in the stands at the match between the Jacksonville Jaguars and Houston Texans.
Amateur footage shows an argument break out between rivals supporters before things really turn ugly.
A man wearing a Texans jersey is suddenly and unexpectedly hit in the side of the head by a Jacksonville fan – while he had his hands down by his side.
The victim went crashing onto the concrete steps in the aisle of the stands – where he proceeded to lie motionless after being knocked out.
A woman who was with the victim then launches herself towards the attacker in anger, as other Jaguars fans attempt to hold her back.
The shocking video was shared to Facebook where it was soon watched more than one million times by disgusted viewers.
Witnesses to the incident say both the woman in the video and the man who threw the punch were escorted out of the stadium by police.