Luis Suarez should slap his thigh, hit a pillow or scream to avoid biting on the pitch, experts advised.

The Uruguayan striker is facing a lengthy ban after being accused of sinking his teeth into Italian defender Giorgio Chiellini during the South Americans' 1-0 victory at the World Cup yesterday.

Pictures showed bite marks on Chiellini's shoulder, while Suarez was seen sitting on the ground holding his teeth immediately after the incident.

Fifa's disciplinary committee said it had opened proceedings against Liverpool forward Suarez - and they have asked his team to present evidence today.

The probe means Suarez - twice previously banned for biting - looks set to be hit with another lengthy suspension despite escaping punishment during the match. Suarez refused to comment on whether he had bitten his opponent.

Experts warned that biting can take years to overcome.

Glasgow Caledonian University sports psychologist Paul McCarthy said it was down to "competing in a pressured environment."

He said: "Biting is an emotional rather than cognitive process, it's a basic response - it's a case of not thinking before acting.

"As a child or baby we bite to express anger but we are quickly taught socially that is wrong. So it is very uncommon and unusual for an adult to behave in that way. I think in sport one of the most high profile incidents was when Mike Tyson bit Evander Holyfield."

Mr McCarthy warned it could take months or years for adults to overcome the behaviour fully.

But he said there are short term fixes.

He said: "As a psychologist we would hope to disengage the person from the action. So he (Suarez) needs to find a way to deal with that anger.

"People can use several techniques - they slap a thigh, some people scream and some people hit a pillow.

Professor Paddy O'Donnell, of the School of Psychology at Glasgow University, said Suarez might need cognitive behavioural therapy.

He said: "My humorous comment would be - three bites and your out.

"What Suarez needs to do is find out what the triggers are. The initial therapy could be nine or 10 sessions but he might have to rehearse intervention techniques for when he's provoked so he can practice not biting."

Stars took to Twitter to voice their disbelief on the incident.

Evander Holyfield tweeted: "I guess any part of the body is up for eating."

Russell Brand said: "Suarez! Your teeth are already prominent, stop biting people!"

Usain Bolt asked: "Did Suarez really bite again?"

Former Liverpool player Michael Owen tweeted: "Tell me I'm seeing things. Surely Suarez didn't bite someone again?"