Mexico have been cleared of improper conduct by their fans following complaints that their supporters used homophobic chants.
The fans' shouts of 'Puto' when the opposing keeper takes a goal-kick is common-place in Mexican football, but anti-discrimination group FARE reported it to FIFA on the basis that it was homophobic language.
A FIFA spokeswoman said: "Disciplinary proceedings were opened against Mexico for improper conduct of spectators during the match, Mexico v Cameroon.
"The FIFA disciplinary committee has decided that the incident in question is not considered insulting in this specific contest. All charges against the Mexican FA have been dismissed"
Mexico head into Monday's concluding Group A clash with Croatia knowing that a third consecutive clean sheet at the finals would be enough to see them through at the expense of their European rivals.
Veteran skipper Rafael Marquez has warned Mexico they face their toughest challenge yet as they attempt to book their place in the second round of the World Cup finals.
FIFA has been contacted by the Fare network relating to discriminatory chanting at the World Cup, the game's governing body has told Press Association Sport.
Mexico will go into their final Group A game against Croatia on Monday with their confidence sky high after a brilliant performance from goalkeeper Guillermo Ochoa against Brazil.
Brazil coach Luis Felipe Scolari was less than impressed with taking only a point against Mexico on Tuesday.