A violent goalkeeper was barricaded in his dressing room by fans after he knocked a referee unconscious in a 'cowardly' attack.
Karl Smith was punched by Aaron Wick on September 22 last year while he was presiding over a match between Horsford and Feltwell.
The incident resulted in Mr Smith suffering multiple fractures. He had to be fitted with a metal plate in hospital, which he will have to wear for life.
Wick, 36, of Staithe Street, Wells, admitted wounding and inflicting grievous bodily harm at King's Lynn Magistrates' Court on Monday.
He has been banned from the game for life.
A report of the incident, compiled by a Norfolk FA disciplinary commission, said Wick's behaviour had no place in society.
Mr Smith said in the report he cautioned Wick earlier in the game over a decision not to award him a free kick.
He said: 'The goalkeeper [Aaron Wick] started ranting and shouting at me for protection. He came right up to my face and was very aggressive.
'I was thinking he was going to head butt me and I took a step back and said 'you don't need to get that close'.
'He said 'I'll get closer than that' and I didn't catch the rest of what he said.'
Mr Smith said Wick swore at him and he issued the player a yellow card.
He said after Feltwell scored its second goal from a corner, the only player to complain was Wick.
'Throughout the game the goalkeeper kept complaining about my decisions along with the centre half,' Mr Smith said.
He later awarded a Feltwell player with a penalty after he was nudged in the back within the area.
'[The] Feltwell player took the penalty and scored, upon which the goalkeeper used foul language towards me,' Mr Smith said.
'I cannot remember what was said but I was making a note in my note book to record the score, the next thing I remember is a policeman kneeling next to me asking if I was okay.'
Feltwell fans 'blocked the exit'
In a statement within the report, Wick said he saw the 'red rage' and struck Mr Smith in the face.
He said as he realised what he had done he asked for people on the side line to call an ambulance.
'Following this I walked to the dressing room to pack all the team kit and my personal belongings and loaded them into my vehicle,' Wick said.
'I had informed people I would pop and hand myself in to the police at Bethel Street, Norwich, after I had returned my car and children to their mother but Feltwell fans blocked the exit.'
He said police later arrived and arrested him.
A report from the Queen Elizabeth Hospital in King's Lynn said Mr Smith suffered a fracture of the left orbit and sinus cavity.
It said an eye witness confirmed he was unconscious for 20 minutes, vomited three times and suffered blurry vision.
The disciplinary commission said Wick's behaviour was 'unacceptable and cowardly'.
Wick had previously been suspended for a 'significant period' for physical contact against a match official in 2015.
The court case
At King's Lynn Magistrates' Court prosecutor Jane Walker said the attack came in a dispute over a red card.
Ms Walker said Wick had previous convictions for violence.
Sentencing guidelines said if convicted, he would be jailed for up to three years.
In mitigation Ruth Johnson, for Wick, said he had admitted the attack from the outset.
'He describes how he simply lost his temper in that flash moment,' she said.
Miss Johnson said Wick had been undergoing hypnotherapy to address his anger management and that had been helpful, but he had had to discontinue the treatment because he could not afford it.
She added she hoped a custodial sentence could be avoided and Wick given the treatment he needed.
A reference from Wick's employer - a local gastro pub - was shown to magistrates before they retired briefly to consider the case.
Chair of the bench, Louise Barber, said the significance of the referee's injury meant the case would have to be sent to crown court for sentence.
Earlier, the court heard Wick had already been subject to an FA disciplinary commission, which had banned him from the game for life.
Wick had faced a previous disciplinary for 'physical contact against a match official' for which he had been suspended for 134 days and fined £75.
The commission voted unanimously to suspend him from all football for life. Wick will be sentenced by the court at a date to be fixed.
Gavin Lemmon, chief executive of Norfolk FA, said: 'It is an appalling incident for us to have to deal with and it has impacted Karl significantly.
'We have a zero tolerance approach on this and the lifetime ban demonstrates that.'
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