A bouncer who knows the staff member in the video has now shared a social media post along with CCTV footage from the bar showing the moments leading up to the attack.
The footage shows the patron taking a wild swing at the bouncer.
Alongside the video he has posted comments in defence of the bouncer's actions, describing him as a "family man".
"I've worked many nights … where we have some people who when we refuse entry don't like it and become aggressive, where we get attacked on the door.
"I know of a night where people pull out knives because we refuse entry.
"We are all family men and all have family to go back to, what everyone doesn't realise whilst we are out providing a safe environment for people to enjoy, who provides a safe haven when people decide to turn against us.?
"Violence is not the first avenue we take, when we working doors we do use our mouth but if you put us in a position where we have to look after ourselves bet your ass we will go down that avenue too."
Wellington police said they were investigating the alleged assault, reported to have occurred shortly before 1am on Sunday on Blair St, Te Aro. No arrests had been made.
Mills said he would be providing the bar's CCTV footage to police.
"While it's in the police's hands we can't comment, but I will say there's more than what you can see.
"We don't take it lightly, we are very upset by it and it will be sorted but we don't want to make any comment - we are not allowed to make any comment until we know exactly what has gone on."
It comes after growing concerns of escalating violence in the Wellington CBD.
Over the same weekend police sought witnesses to a serious assault in the middle of Courtney Place at 2.45am on Saturday, which left a man seriously injured.