France striker Thierry Henry is to be investigated by Fifa's disciplinary committee over his handball against the Republic of Ireland last month.
The Republic failed to qualify for the 2010 World Cup, losing 2-1 on aggregate to an extra-time goal, courtesy of the assist by Barcelona's Henry.
Fifa's executive committee met on Wednesday to consider the incident as part of a disciplinary crackdown.
Fifa said there was no certainty Henry would be banned if found guilty.
The governing body's president Sepp Blatter told a news conference: "I have not said that Thierry Henry will be punished, I have said that Thierry Henry will be examined by the disciplinary committee of Fifa."
Asked why Fifa were making a special case of Henry, Blatter replied: "This is a matter of the disciplinary committee and it's not a question of this player or another - it was a blatant unfair playing and was shown all around the world, but I don't know what the outcome will be."
Blatter said players and managers should be aware that the "eyes of the world" would be on them in South Africa next summer.
"I appeal to all the players and coaches to observe this fair play. In 2010 we want to prove that football is more than just kicking a ball but has social and cultural value," he said
"So we ask the players 'please observe fair play' so they will be an example to the rest of the world."
Henry twice handled the ball before crossing to William Gallas, who scored the equaliser against the Republic in the play-off in November to put France into next year's finals.
On the back of the furore surrounding the incident, Fifa met at Cape Town to consider goal-line technology and extra referees at the World Cup.
However, the sport's governing body decided against using additional referees in South Africa and have instead opted to set up an inquiry into the benefits of video technology and extra officials.
Henry handles the ball before setting up France's equaliser
Fifa were also initially asked to consider the Republic's plea for an extra place in the finals, but the Football Association of Ireland (FAI) withdrew that request before the executive committee met.
Ahead of Fifa's announcement that they would investigate the handball incident, the FAI were critical of Blatter.
The Irish were irked after the Swiss made public details of what the FAI claimed were private discussion.
In a statement, the FAI said the bid to be included as a 33rd team at the World Cup was "peripheral, was not raised in any of its formal written submissions to Fifa, and was explored only fleetingly as part of a wide-ranging 90-minute discussion with that body.
"Instead of diverting attention, we would prefer that Mr Blatter uses this opportunity to deal with the issues which have been raised formally for the benefit of football worldwide."
The FAI also demanded that tournament rules be not changed halfway through, and championed the introduction of video replays and goal-line assistant referees.
The Irish were already at odds with Fifa over the late decision to seed the play-offs, which meant they could only be drawn against France, Portugal, Russia or Greece, rather than fellow second-place qualifiers Bosnia-Herzegovina, Slovenia or Ukraine.
I have nothing against the Irish, they were very sporting when they came to FIFA
Blatter has since apologised for his comments made earlier on in the week, which suggested the Republic's request to be included in the World Cup had not been considered seriously.
"I would like to express my regrets to a wrong interpretation of what I said and to the FAI, I'm sorry about the headlines going around the world," he said.
"I have nothing against the Irish, they were very sporting when they came to Fifa."
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