Premier League footballer Joey Barton has admitted assaulting a former team-mate in a training ground row.
The Newcastle United midfielder changed his plea ahead of a trial and admitted assaulting Ousmane Dabo during a training ground row on 1 May last year.
The 25-year-old repeatedly punched Dabo as he lay dazed on the ground, Manchester Minshull Crown Court heard.
The ex-Manchester City player is currently serving a six-month jail term for an attack in Liverpool.
The trial, which had been due to start more than a year after the incident, was put back until after the season had ended for the convenience of witnesses.
Many of them are involved in professional football.
Outlining the events at Manchester City's training ground on May 1 last year, prosecutor Richard Vardon said it was an "explosive combination of football and violence".
Ousmane Dabo was in court to hear Barton admit the attack
Barton and Dabo confronted each other after a row during a training match, the court was told.
Dabo, 31, was said to have felt intimidated that Barton had invaded his personal space as he shouted and swore at him.
The Frenchman pushed his shoulder with both hands and Barton retaliated by punching him in the head, causing the Frenchman to fall over and lose consciousness.
Mr Vardon said several witnesses said Barton continued to punch Dabo while he lay on top of the player, who was in a dazed state.
One player, Georgios Samaras, said he had never seen such a violent incident on a training pitch in all his career, the prosecutor added.
Barton, who admitted one charge of assault occasioning actual bodily harm (ABH), will be sentenced on Tuesday.
It is the third time Barton has been in court during 2008.
Barton changed his plea and admitted assaulting Oussmane Dabo
In May Barton was jailed after an attack in Liverpool which took place two days after Christmas.
CCTV images showed the footballer punching a man 20 times.
Later in May Barton was cleared of vandalising a taxi during a night out in Merseyside.
The Liverpool-born footballer was sold by City to Newcastle in a £5.8m deal last summer, signing a five-year contract.
Newcastle United said it was not commenting on Monday's hearing.
Dabo, 31, is now playing for Rome side Lazio and was in court to hear Barton plead guilty.
This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.