NATAL, Brazil - Uruguay star Luis Suarez faces expulsion from the World Cup for biting as FIFA confirmed it had opened disciplinary proceedings against the player on Wednesday.
Suarez, banned twice before for biting players, appeared to sink his teeth into defender Giorgio Chiellini on Tuesday during Uruguay's 1-0 win over Italy.
Uruguayan players and team officials pleaded ignorance but the incident was captured clearly on television footage, making a ban almost inevitable.
"FIFA can confirm disciplinary proceedings have been opened against the player Luis Suarez," FIFA said in a statement.
Suarez and the Uruguayan Football Association can submit evidence to investigators until 5:00pm (2100 GMT) on Thursday, FIFA added.
Suarez, who plays in the English Premier League for Liverpool, is one of the world's biggest stars, and could be banned for up to 24 games under FIFA rules.
He has already received long bans for biting during his club career as well as racially abusing Manchester United player Patrice Evra during a game in 2011.
The latest flashpoint in his chequered career occurred towards the end of Uruguay's Group D game with Italy.
Replays showed Suarez appearing to bite Chiellini's shoulder as the two players made contact in an off-the-ball incident.
Chiellini angrily remonstrated with Mexican referee Marco Rodriguez, pulling his shirt off his shoulder to show red marks on his neck.
Afterwards a disgusted Chiellini told Italian television: "He bit me, it's clear, I still have the mark." "The referee should have blown his whistle and given him a red card," he added.
Suarez sought to play down the incident in comments to Uruguayan television, claiming Chiellini had barged him.
"There are things that happen on the pitch and you should not make such a big deal out of them," Suarez said.
Tabarez 'didn't see' bite
Uruguay's veteran manager Oscar Tabarez pleaded ignorance of the incident.
"I didn't see it. I'd like to see the images first," he told a press conference.
Tabarez also suggested Suarez was being victimised by journalists.
"He is the preferred target for a lot of media," Tabarez said.
Pressed on the issue, a visibly irritated Tabarez refused to condemn Suarez. "This is a football World Cup, it's not about cheap morality." Senior FIFA officials wasted no time in condemning the striker.
"There is no doubt Luis Suarez is a fantastic footballer but once again his actions have left him open to severe criticism," FIFA vice-president Jim Boyce told the BBC.
"FIFA must investigate this incident very seriously and take whatever action is deemed necessary."
If found guilty by FIFA disciplinary chiefs, the incident means the end of the tournament for Suarez, lambasted during the 2010 World Cup for his goal-line handball which denied Ghana what would have been a quarter-final victory.
In November 2010 he was banned for seven matches by the Netherlands FA after biting PSV Eindhoven's Otman Bakkal on the shoulder when he played for Ajax.
Suarez was dubbed "the Cannibal of Ajax" by Dutch media.
In April 2013, he was given a 10-match ban by the English FA after biting Chelsea defender Branislav Ivanovic in a match at Anfield.
He was also banned for eight matches in 2011 for racially abusing Manchester United's Patrice Evra.
"This is behaviour that's happened two times (before). You cannot justify it. I seriously think he needs help," said Everton manager Roberto Martinez, reflecting the shock felt through the football world and yet another Suarez transgression.
Italy, who had Claudio Marchisio sent off in the second half, join a growing number of European sides on the World Cup scrapheap after the exit of Spain, England, Croatia and Bosnia.
England exit with whimper
In Group D's other game in Belo Horizonte, Costa Rica ensured England's miserable World Cup ended with a whimper in a 0-0 draw.
The result meant Costa Rica win the group, unbeaten after three games, with Uruguay finishing as runners-up.
Costa Rica will play Group C runners-up Greece on Saturday after they scored a last-gasp 2-1 win over Ivory Coast to scrape into the last 16.
An injury time penalty from Georgios Samaras clinched victory for the Greeks and left Ivory Coast players shattered.
Colombia wrapped up qualification for the last 16 with another impressive win, destroying Japan 4-1 in Cuiaba.
Colombia will now face Uruguay, almost certain to be without Suarez.