Luis Suárez could receive another lengthy suspension after he appeared to bite Chelsea defender Branislav Ivanović during Liverpool's Barclays Premier League draw on Sunday.
In the 65th minute, Suárez and Ivanović were involved in a collision inside Chelsea's penalty area which led to a Liverpool corner, however replays showed Suárez sink his teeth into the Serbian's arm.
Suárez was suspended for seven matches in Holland in 2010 when, while playing for Ajax against PSV Eindhoven, he bit Otman Bakkal.
It capped an eventful afternoon for the polarising striker, who assisted a goal for Daniel Sturridge, conceded a penalty after punching the ball and scored a 97th minute equaliser to deny Chelsea victory.
Only this morning Suárez told The Sunday Times how his wife was encouraging him to improve his on-pitch discipline.
Controversy has followed Suárez since he came to prominence at the 2010 World Cup, when he handled on the line in the final minute of extra-time to prevent Ghana from beating Uruguay in the quarter-final. He was sent off but Asamoah Gyan smashed his penalty against the crossbar, with Suárez's gleeful reaction caught on camera. Uruguay won the penalty shootout.
Since he joined Liverpool, he has served a one-match suspension for sticking his middle finger up at Fulham fans in December 2011 and most infamously, he was banned for eight matches for racially abusing Manchester United defender Patrice Evra last season.
When Suárez came face-to-face with Evra months later, he refused to shake his hand and was further condemned. He issued an apology the following day, but has never said sorry to Evra.
The 26-year-old was accused of cheating in the third-round of the FA Cup in January when he handled to control the ball before scoring the winner at Mansfield Town.
He is also currently under investigation by Fifa for allegedly punching Chilean Gonzalo Jara during a World Cup qualifying defeat last month and has already escaped a Uefa club ban after he appeared to stamp on the back of Zenit St Petersburg defender Tomáš Hubočan.
Liverpool manager Brendan Rodgers said earlier in the campaign Suárez would be dealt with "internally" after his striker admitted to diving during an interview.
UPDATE: Suárez has apologised for biting Ivanović this evening.
"I have issued an apology and have tried to contact Branislav Ivanović to speak to him personally," Suárez said. "I apologise also to my manager, playing colleagues and everyone at Liverpool Football Club for letting them down."
The club's managing director Ian Ayre commented: "Luis has made an unreserved apology for his actions today.
"His behaviour is not befitting of any player wearing a Liverpool shirt and Luis is aware that he has let himself and everyone associated with the club down. We will deal with the matter internally and await any action from the FA."