The brother of Socceroos star Tim Cahill has been jailed for six years in Britain for assaulting a man who was left partially blind from the attack.

Sean Cahill, 29, was found guilty of causing grievous bodily harm with intent by a jury in a London court last November.

Croydon Crown Court judge Robert Rhodes sentenced Cahill to six years in jail, saying his attack on 31-year-old Christopher Stapley during a brawl near a south London nightclub three-and-a-half years ago was "extremely serious".

Cahill, who stood stony-faced with his hands folded in front of him as his sentence was read out, will be able to apply for bail after three years.

Before being led out of the courtroom, Cahill was hugged and kissed by his mother Sisifo, who returned to her seat and sobbed while being comforted by friends.

During his trial last year, Cahill denied kicking Mr Stapley in the face during the brawl outside a taxi office in Bromley, Kent, after leaving a local nightclub in the early hours of July 11, 2004.

Judge Rhodes said he had taken into account Cahill's previous good character and "impressive" personal references before deciding to give him a jail sentence, which he said was the minimum available.

"It is very sad to see a young man with so much good in him ... convicted of this extremely serious offence," the judge said.

"But ... you ran and kicked a defenceless man who was on the ground at least twice.

"You kicked him in the face and his injuries were terrible."

During the trial last November, the court heard that a fight had erupted between a group of friends Cahill was with and another crowd of men with Mr Stapley.

Cahill denied having hurt Mr Stapley and claimed he only got involved in the brawl to try to defend his brother Chris.

Cahill's younger brother and Everton goal-scoring star Tim Cahill did not attend the trial and was not in court.

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