PGA Tour of Australasia officials said on Friday that Grant Buchanan and Matt Kelly, the caddies of James Nitties and Marc Leishman respectively, had to be separated after coming to blows as their players prepared for their opening round.
Tournament director Andrew Langford-Jones said "we've spoken to those involved and we still need to speak to a few more people."
In a statement Friday, Langford-Jones said a decision on any disciplinary action would be determined within a week.
"Our members in no way condone this behaviour, and we are saddened the incident has drawn attention away from this great tournament," he said.
Leishman had a 2-under-par 70 on Thursday, four strokes behind leader John Senden.
Nitties, who has just returned from California and an unsuccessful attempt at securing his U.S. PGA Tour card for 2013, shot 77.