Cricket Australia said Monday it was probing a heated exchange between David Warner and South Africa's Quinton de Kock in a stairwell during the first Test in Durban.
Video footage of the clash on Sunday, broadcast in Australia, showed Warner pointing and directing a verbal barrage at de Kock before he was restrained and pulled away by his teammates.
The incident reportedly took place as the players were returning to their dressing rooms at tea on day four of the first Test.
"CA (Cricket Australia) is aware of reports of an incident between players in Durban," a Cricket Australia spokesman said in a statement.
"CA is working to establish the facts of what has occurred and will not be commenting further until that has been done."
The Australians had earlier been criticised for their ebullient celebration of the dramatic run-out of Proteas' star batsman AB de Villiers.
De Villiers was run out for nought after being involved in a mix-up with opening batsman Aiden Markram, with Warner playing a key fielding role in securing the crucial wicket.
The vice-captain then led ecstatic celebrations with his teammates as Nathan Lyon, who had knocked off the bails, dropped the ball towards a sprawled de Villiers as he ran over to join them.
In a statement issued by Cricket South Africa on Monday, team manager Mohammed Moosajee said: “It’s rather unfortunate that the incident took place and certainly not in the spirit of the game.
"The match referee had spoken to us after the day’s play. We will await any further communication from the ICC around this incident.”
The Australians' behaviour was slammed by former South African captain Graeme Smith, who told Cricket Australia's cricket.com.au website in Durban that Lyon as an experienced cricketer would "probably say (his action) was unnecessary himself".
"We've got used to Davey (Warner) over the years. I think the less interest you take in him the better," Smith added.
"He can be a bit of a fool at times. It's best just to let him be."
Australia finished the fourth day one wicket short of victory with South Africa on 293 for nine, needing 417 to win, when bad light ended play at Kingsmead.