Barton (right) attacked Dabo (left) in a training ground incident
Newcastle's Joey Barton has been banned for six games by the Football Association, with another six suspended, for assaulting Ousmane Dabo.
Barton, 26, had previously admitted the charge of violent conduct and was fined £25,000 at the personal hearing.
He will be banned for another six games if he is found guilty in the future.
In July Barton received a four-month suspended prison sentence for the assault in May 2007, when the pair were team-mates at Manchester City.
The disciplinary panel revealed its findings at a the three-hour hearing at the Football Association's headquarters in Soho Square, London.
Former Newcastle boss Kevin Keegan, who quit on Thursday, faxed his support but did not appear in person as a character witness for Barton.
Barton will miss the next six Newcastle games against Hull, West Ham, Tottenham (in the Carling Cup), Blackburn, Everton and Manchester City.
If fit and ready, he could return at Sunderland on 25 October.
Since the training ground assault on Dabo, who now plays for Lazio, Barton has been jailed for a drunken attack on revellers in Liverpool city centre.
The commission members considered principally the serious attack by Mr Barton that clearly cannot be accepted
Maurice Armstrong, independent regulatory commission chairman
Barton was released from prison in July after serving 74 days of his sentence for attacking a teenager.
A statement from the independent regulatory commission chairman Maurice Armstrong said: "Much has been written about Mr Barton over recent months.
"The regulatory commission had the benefit of taking all appropriate information into consideration.
"The commission members considered principally the serious attack by Mr Barton that clearly cannot be accepted.
"The members also had to take into consideration the sanctions imposed by the courts and the pro-active support Mr Barton has received from Newcastle United and other professional bodies.
"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 judgment."
The training ground attack left French midfielder Dabo with several cuts and bruises as well as a suspected detached retina.
He said it was so bad it left him "looking like the elephant man".
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