Newcastle United midfielder Joey Barton has been banned for 12 games, six of them suspended, for attacking a team mate while at former club Manchester City.

Barton received his punishment, which takes immediate effect, at a Football Association disciplinary hearing on Friday after admitting a charge of violent conduct against Ousmane Dabo. He was also fined 25,000 pounds.

The 26-year-old has already received a four-month prison sentence, suspended for two years, for the attack.

Barton will have to serve the further six-match ban should he commit any other offence involving violence or get sent off for violent conduct before the end of the 2009-10 season.

"The Commission members wanted to punish the offence appropriately but give Mr Barton an opportunity to ensure his professional conduct does not falter again and ensure he is fully aware of the consequences should he make another serious error of judgement," Independent Regulatory Commission chairman Maurice Armstrong said in an FA statement.

Barton, who has been capped once by England [Images], attacked Dabo at Manchester City's Carrington training ground in May 2007, leaving him with a scratched retina, facial bruising and stitches in a cut under his eye. Dabo, who now plays for Lazio, said he had been left looking like "elephant man".

City suspended Barton for the remainder of the season before he signed for Newcastle last June.

At the time of being sentenced for his assault on Dabo, Barton was already serving a six-month prison term for an attack on a teenager in Liverpool city centre in December 2007. He was released in July after 74 days in prison.

Kevin Keegan, who resigned as Newcastle manager on Thursday, had offered his support to Barton and submitted evidence to Friday's hearing, although he did not appear in person.

(Reporting by Martyn Herman; Editing by Trevor Huggins)

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