The NBL is now meeting with the Illawarra Hawks to determine the fate of a fan who poured beer on Sydney Kings import Marcus Thornton during the match on Wednesday night.

Meanwhile, the company which rented the corporate box, Figtree Private Hospital, released a statement to Fox Sports on Thursday apologising for the incident and saying the man has a "cognitive impairment".

"Figtree Private Hospital has apologised to the Sydney Kings and the Illawarra Hawks for the actions of an elderly gentleman who was a guest in the hospital's box last evening," hospital chief executive Paul McKenna said in the statement.

"The 83-year-old father of a long-term, valued employee, has some cognitive impairment and does not recall the incident. His family are very regretful of the incident and have indicated they will be making a formal apology on his behalf."

The hospital said the woman in the video is the man's daughter.

The league released a statement on Thursday saying they will not permit what Kings coach Damian Cotter labelled "dropkick behaviour," and are looking to act swiftly on the matter.

"The National Basketball League (NBL) will not tolerate behaviour by any person that jeopardises player safety," it said.

Marcus Thornton was shocked when he had beer poured on his hair by a fan. ( Youtube )

"The NBL places the utmost importance on the safety and well-being of its players.

"NBL General Manager Jeremy Loeliger is currently in Wollongong and will be reviewing the incident with Illawarra Hawks staff and venue management this morning."

Captured on live television just days after the A-League banned almost 200 fans, the man's act of leaning over a sponsor's signage and showering Thornton with beer created a wave of reaction on social media.

The incident occurred after Thornton drove to the basket midway through the third quarter, falling to the floor and almost sliding into the advertising sign.

As the American guard looked up hoping for a foul call, the offender poured beer in Thornton's hair.

"That has to be dealt with," Cotter said.

"I'd be really ashamed if my club did that.

"This is 2015, not 1974. That's all I should say about it. But that's dropkick behaviour. I mean, really, how unsophisticated and how much of a drongo do you want to be? It shouldn't happen in the first place."

Hawks coach Rob Beveridge said many players didn't mind some verbal interaction with fans.

But the former Perth Wildcats coach was disappointed that line was crossed on Wednesday night.

"There's nothing wrong with a bit of banter and hometown sledging of the opposition, but what happened tonight was just plain stupid and disrespectful, and fans have to remember what is and what isn't acceptable behaviour," Beveridge said.

"I fully endorse the decision to eject the bloke. That's the only option available when something like that happens and escorting him out for everyone to see sends a clear reminder to all fans.

"The good thing is that the overwhelming majority of basketball fans understand and accept those boundaries and we're lucky that those kinds of things very rarely occur. I'm confident it was a one-off situation that won't happen again."

Illawarra's win boosted their record to 5-6 ahead of Saturday night's second leg of their round eight double - a home game against Townsville.

Beveridge will still be without regulars Tyson Demos, Cody Ellis and Rhys Martin and hopes to have the injured trio back for next week's round nine meeting with competition leaders Melbourne.

The Kings remain last on the ladder with three wins from 12 games.

AAP/ABC