Brumbies players were quizzed by officials on Monday about what was said in heated exchanges which led to an investigation into Potgieter's offensive sledge.

It's understood some Brumbies players were asked to provide details to SANZAR, Super Rugby's governing body, after David Pocock made on-field complaints to referee Craig Joubert about Potgieter's insults.

Potgieter apologised on Monday night for any offence caused by his comments and was fined $20,000 by the ARU, $10,000 of that suspended.

It's understood that Potgieter used similar slurs in the Brumbies-Waratahs matches last year and the ACT players decided to take a brave stance against homophobia.

The South African back-rower will be required to undergo educational and awareness training.

The Brumbies were privately frustrated that Pocock and the club were cast as the bad guys for bringing the issue to light, despite Potgieter's actions causing the incident.

SANZAR passed its investigation on to the ARU, who took control of punishment and ARU boss delivered the verdict and Potgieter's fine on Monday night.

It's understood Potgieter used the word faggot to sledge two Brumbies players - one believed to have been Nic White - in the second half of the Waratahs' 28-13 win on Sunday.

Brumbies players decided enough was enough after hearing Potgieter use similar language a year ago.

Both Pocock and Brumbies captain Stephen Moore raised concerns with Joubert, who then addressed the issue with stand-in Waratahs captain Michael Hooper.

"You just can't say those things ... David felt he was protecting his teammates and showing that you can't say those things," Brumbies chief executive Michael Jones said.

"[Moore] backed up [Pocock] and I'm quite proud of the way the guys handled it last night and today. I'm quite proud of the way the Brumbies came out of this.

"I'm sure there were suggestions that we had broken the code of what happens on the field, stays on the field. But the reality is, it stayed on the field for us. The system works."

Brumbies coach Stephen Larkham said there was no room for homophobic language in sport or society.

"The decision was made by SANZAR and the ARU and they've taken everything into consideration, we have full confidence in that decision," Larkham said.

"I certainly am very proud of the boys and of the way they handled it. There's no need for that sort of language in professional sport or anywhere in society."

The incident will add extra spice to the return Australian derby when the Waratahs play the Brumbies in Canberra on May 1.

Super Rugby officials spent Monday sifting through audio clips and video footage to see if there was enough evidence to mount a case against Potgieter.

Potgieter later admitted to making comments contrary to the ARU's inclusion policy.

The Brumbies opted not to lodge a formal complain, with Joubert citing the incident in his match report and SANZAR officials taking control of the investigation.

Pocock expressed his disappointment on the field and then again after the match, saying that it's up to the players to "quell that sort of language".

The ARU signed an inclusion policy last year to stamp out all forms of discrimination and homophobia in rugby.

But the test of its policy will be how it reacts to SANZAR's investigation.

ACT Chief Minister Andrew Barr implored rugby union officials to "get tough" in a bid to stamp out homophobia in sport, declaring he's "proud of the Brumbies" and team's actions will help instigate change.

Barr, who is the first openly gay state or territory leader in Australia, applauded the Brumbies for taking a stance against the slurs.

"The Brumbies are taking a stance for the right reasons, I commend them for raising it on the field," Barr said.

"It may well be controversial, but in the end things will only change if people speak up and speak up loudly. I'm glad it hasn't been swept under the carpet, and if the allegations prove to be correct there's a cultural challenge ahead.

"But the only way it will ever change is if people are called out and there is an example made that this is wrong."