Luis Suarez's lawyer flew to Rio de Janeiro on Wednesday to present his defense after the Uruguay striker appeared to bite a player during his team's 1-0 victory over Italy, leaving him facing a lengthy ban if found guilty by soccer's governing body.
The incident in Natal on Tuesday has brought the ugly side of the game to the fore, marring a tournament that has been widely praised for its attacking football and major upsets.
Suarez, who has been banned from soccer twice previously for biting, has until 5:00 pm local time (2000 GMT) on Wednesday to present his case to FIFA.
"We're polishing off a defense argument," his lawyer Alejandro Balbi told local radio in Uruguay, where many people support the gifted frontman and feel he is being unfairly singled out by media in Europe.
"We don't have any doubts that this has happened because it's Suarez and secondly because Italy was eliminated," added Balbi, who is also a Uruguay FA board member. "There's a lot of pressure from England and Italy."
The incident came 10 minutes from time in Uruguay's Group D game against Italy, when television footage appeared to show Suarez sink his teeth into the shoulder of Italian defender Giorgio Chiellini, who has publicly accused him of biting.
The Italians were still complaining when Uruguay's Diego Godin scored with an 81st-minute header to secure a win that sent the South Americans through to the last 16 and eliminated four-times champions Italy from the tournament.
Chiellini pulled down his shirt, and Reuters photographs showed what appeared to be bite marks on his shoulder.
The referee did not spot the incident during the match, but FIFA's rules allow the use of video or "any other evidence" to punish players retrospectively.
FIFA's disciplinary code sets a maximum ban of 24 matches or two years, but the longest suspension FIFA has imposed for an offence at a World Cup was eight games for Italy's Mauro Tassotti for breaking the nose of Spain's Luis Enrique in 1994.
Uruguay could potentially play four more games in the tournament, and it would be a surprise if Suarez were to be given a ban of a shorter duration if found guilty.
FIFA said it would work as quickly as possible in its investigation into the incident, with Uruguay due to play Colombia on Saturday in Rio de Janeiro in the first knockout round.
"The Disciplinary Committee understands the urgency of the matter," FIFA spokeswoman Delia Fischer told reporters.
"It is working to get and assess all elements in order to make a decision as early as possible, particularly given the fact that Uruguay are still in the tournament.
"We will get an update to you later today or tomorrow or whenever they take their decision," she said.
Brazil's sports minister Aldo Rebelo said the incident was "regrettable" for its potential impact on the World Cup.
"I think it's very bad that it happened," he told reporters. "He (Suarez) is an exceptional player, helps to give the World Cup more attention ... That was not the first bite. Other ones have happened."
Losing Suarez would be a huge blow to Uruguay, who rely heavily on the prolific Liverpool forward's attacking talent. He scored both goals in the side's 2-1 win over England earlier in the tournament, and is widely considered the team's best player.
Suarez has denied biting Chiellini.
"Those are situations that happen on the pitch. We were both just there inside the area. He shoved me with his shoulder, and my eye got left like that also," he said on Tuesday, in reference to Chiellini's marks.
Balbi, who is traveling to Rio de Janeiro with Uruguay FA boss Wilmar Valdez to present their case to FIFA, echoed those remarks.
"There is a possibility that they ban him, because there are precedents, but we're convinced that it was an absolutely casual play, because if Chiellini can show a scratch on one shoulder, Suarez can show a bruised and almost shut eye," Balbi said.
"We're going to use all the arguments possible so that Luis gets out in the best possible way."
Whatever the outcome of FIFA's investigation, the biting accusations could have an impact on Suarez's commercial value as one of the world's top strikers.
Poker brand 888 said on Wednesday it was "seriously reviewing" its sponsorship agreement with him after Suarez became one of the online gambling company's brand ambassadors last month.
Suarez has an endorsement deal with German sportswear company Adidas, and he has also been advertising the Beats headphones worn by many top players.
Support at home
Opinion in Uruguay, a country of around three million people sandwiched between soccer powerhouses Argentina and Brazil, was divided over Suarez's latest antics.
The 27-year-old is regarded as something of a hero at home, having grown up in a poor family in the northwestern city of Salto, where he looked after parked cars to help support his siblings after his parents split up.
"We needed to win, so if you have to hit you hit, if you have to bite you bite," said Barbara Giordano, a 26-year-old law student in Montevideo.
Local media also complained about reaction to the incident round the world.
Leading newspaper El Pais honed in on what it called a "very tough" attitude from English media towards Suarez and highlighted that the player's apparent bruised eye did not receive much attention.
Some Uruguayans, however, were furious.
"This kid can't control his biting and attacking issues," said Luis Lara, a 52-year-old shopkeeper. "That makes all of us Uruguayans look bad."
On Wednesday morning, British newspapers offered a range of headlines reading "Chewy Luis," "Chew Dirty Rat," "Animal Suarez," "3 Bites and You're Out," "Kop Crisis as Suarez Faces Two-Year Ban for Sinking Teeth into Defender," "Kick Suarez Out of Finals, Says Chiellini," "Ban This Monster," and "Jaws III."
Suarez's indiscretion also sent the world's social media into meltdown and within minutes of the match ending #Suarez was one of the top-trending hash tags on Twitter.
Suarez, England's Footballer of the Year, scored both goals in Uruguay's 2-1 victory over England having missed the opening match as he recovered from knee surgery, and until the incident had kept control of his temper during a bruising game.
Germany's Kahn, former biter, weighs in
Oliver Kahn, who once nibbled on the neck of a Bundesliga opponent and went after another with a kung-fu-style kick in the same game, believes he understands what is going on inside the head of the Uruguayan striker.
The former Germany goalkeeper escaped punishment for the twin outbursts against Borussia Dortmund in a 1999 Bundesliga match. A decade later Kahn admitted he was under so much strain at the time that he lost control.
"That kind of behavior is usually associated with animals," said Kahn of Suarez.
"In my mind, that's the wrong way to channel your internal tensions," added Kahn, who is now working as a pundit for Germany's ZDF television at the World Cup in Brazil.
"We saw in the last match [against England] that he was nearly crying. Perhaps that behaviour was a last desperate attempt to release some of the enormous pressure building up inside him and it was the only way to let some of the tension out. For me, there's no other explanation."
Kahn is remembered in Germany not only for his heroics for Bayern Munich, whom he led to the 2001 Champions League title, and his 86 caps for Germany, but also for nibbling on the neck of Dortmund's Heiko Herrlich and going after Stephane Chapuisat in the same match.
It took more than a decade for Kahn to admit that he made a mistake.
"That was the zenith of my aggression and it erupted inside of me," Kahn told the Sueddeutsche Zeitung in 2010.