Police said a 24-year-old Wyong man was allegedly punched in the back of the head during an argument in the car park of the Woodport Inn hotel in Erina at 12.45am on Saturday.

The punch caused him to fall and strike his head on the pavement.

When paramedics arrived at the scene, the man was unconscious.

The victim was taken to Gosford hospital with serious head injuries. He was later transferred to Royal North Shore Hospital where he remains in a serious but stable condition.

Police said that at around 2.30pm on Saturday a 22-year-old man was arrested at a home at Long Jetty and charged with causing grievous bodily harm to a person with intent.

He was refused bail and will appear at Gosford Local Court today.

The hotel had been hosting Australian electro DJ Timmy Trumpet at the time.

Trumpet said the news was devastating.

"It's truly heartbreaking to hear about something happening like this and my thoughts are with him, his family and his friends. I'm against violence in any capacity and incidents like this are exactly why."

In January this year, the NSW government instituted lock-out laws in Sydney's CBD entertainment precinct following the deaths of two young men caused by "one-punch" assaults.

The Woodport Inn was listed by the Office of Liquor, Gaming and Racing as one of NSW's 16 most violent venues in 2013. It was removed from the list in June this year.

The pub has a 2am curfew and a 4am closing time, according to its Facebook page.

The hotel has declined to comment.

Police are appealing for any information that might help identify the other man involved in the altercation.

He is described as being of solid build with a shaved head and was wearing dark pants and a white shirt.

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