FIFA have confirmed that they will open a disciplinary investigation into the circumstances surrounding Zinedine Zidane's sending-off in France's World Cup final defeat by Italy.

Zidane was sent off in extra-time in Berlin for a head-butt on Azzurri defender Marco Materazzi, after the two players had clashed verbally following a free-kick to France.

A statement from FIFA confirmed: "FIFA will open a disciplinary investigation into Zidane's conduct to enable it to clarify the circumstances surrounding the incident as exactly as possible."

Materazzi has been accused of serious verbal abuse of Zidane in several media reports, but the centre-back has played down his role in the incident.

He told Gazetta dello Sport: "I held his shirt for a few seconds only, then he turned to me and talked to me, jeering.

"He looked at me with a huge arrogance and said 'if you really want my shirt I'll give it to you afterwards'. I replied with an insult, that's true.

"It was one of those insults you're told dozens of times and that you often let fall on a pitch.

"I did not call him a terrorist. I did not bring up Zidane's mother, for me a mother is sacred."