A feud between two rival millionaire polo club owners and neighbours has allegedly erupted into violence after one accused the other of headbutting him.

Millionaire John Marshall, owner of the Kurri Burri Polo Club, faced Parramatta Local Court on Wednesday after being accused of headbutting Peter Higgins.

Mortgage Choice co-founder Mr Higgins owns the Sydney Polo Club, which flanks Marshall's Kurri Burri Club.

The pair have been at loggerheads for months, with the fence between the neighbouring clubs dubbed the 'Gaza Strip' by punters and astounded locals.

The court heard that Marshall allegedly drove onto Mr Higgins' property before walking towards him with his 'arms out' on March 29.

Grant Brady SC, representing Marshall, said he would not dispute that Mr Higgins did receive a 'blow to the nose' but he argues his client was only acting in self defence, The Sydney Morning Herald reported.

'The accused is saying he was threatened and intimidated by Mr Higgins and was acting in a way that he came to because he believed he was acting in self-defence,' he told the court.

He also argued the appearance of Mr Higgins' son, allegedly shirtless and aggressive, intensified the situation and led to Marshall feeling threatened, before he left the property.

The feud between the two millionaires erupted after Mr Higgins claimed that Marshall was 'jealous' because he was trying to block him from hosting the World Polo Cup at his property near Sydney.

Mr Higgins, the co-founder of Mortgage Choice, won the rights to hold the international event on his expansive Richmond estate which featured in the 2013 blockbuster film The Great Gatsby.

'He looks across the fence and sees a property four times greater than his. I can only put it down to jealousy,' Mr Higgins said in March 2017.

'Why else would he have gone out of his way to thwart what we are trying to achieve.'

After the Hawkesbury City Council declined an application for Mr Higgins' polo club to host weddings, he once again laid the blame with his polo club neighbour.

'It has been difficult having such a neighbour who seems to make it his life to try and wreck ours, however I can assure you he will not be able to stop the world polo championship going ahead October, 2017,' Mr Higgins said at the time.

But Marshall - the chairman of Marshall Investments claimed the event was just a 'Trojan Horse' so Mr Higgins could develop his property, a claim the owner flatly denies.

The feud is so intense onlookers have described the country road that borders the rolling fields of their properties as 'the Gaza Strip'.

'On one side of the Gaza Strip is complete integrity,' Mr Marshall told Daily Mail Australia.

The hearing is expected to continue at the Parramatta Local Court in October.