Newcastle midfielder Joey Barton will serve a minimum six-match ban and has been fined £25,000 by the Football Association for his attack on former team-mate Ousmane Dabo last May.
The full length of Barton's ban is 12 games but six of those are suspended until the end of the 2009-2010 season.
The 26-year-old was given the punishment by an independent disciplinary panel on Friday afternoon for last year's altercation with Dabo when both were players at Manchester City.
The four-man panel, which included former England manager Graham Taylor, took just under two hours to reach their verdict, which now sees Barton ruled out of action until October 25 at least.
He had previously admitted the charge of violent conduct in August, but requested a personal hearing in an attempt to plead leniency. He has now has two weeks to appeal the verdict.
A statement on the FA's website read: "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 FC 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 judgement."
The attack left Dabo, who now plays for Italian club Lazio, with several cuts and bruises as well as a suspected detached retina.
The France midfielder said the attack was so bad that it had left him 'looking like the Elephant Man'. In July, Barton received a four-month suspended prison sentence for the assault.
Barton was jailed for six months in May for a separate assault on a man in Liverpool last December.
His former boss Kevin Keegan, who resigned on Thursday, was scheduled to attend the hearing as Barton's character witness but is thought to have submitted a character statement by fax instead.