The Liverpool star appeared to bite the defender during a tussle in the Italy area, with the Juventus man attempting to show the referee the mark on his shoulder following the incident.
Images circulated on social media showing the damage seemingly caused by Suarez after the match, but Lugano insists the Azzurri defender already had a scar from a previous incident and has branded the player "a coward."
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"Are you sure you saw a bite?" Lugano asked reporters when questioned. "Because I've watched the incident again and I saw nothing. ... I've seen the picture of Chiellini. That scar isn't from today's game. You have to be very stupid to believe that scar is from now.
"Italy had been wasting time the entire match, provoking us on the pitch like they always do. I never believed an Italian player could be such a coward off the pitch. During the game, yes, it is all part of football, but I think the manly thing to do would be to just accept defeat. To denounce your opponents just out of bitterness is bad. There was no bite and there was no scar."