Five-star man: Kagiso Rabada celebrates one of his five wickets with teammates on the first day of the second Test at St George's Park on Friday.
Should the ICC match referee feel there is sufficient evidence to charge Rabada with a Level 2 offence, which equates to three demerit points, he could be ruled out of the remainder of the series.
Rabada now has five demerit points to his name, having picked up a third sanction by the ICC in the past 12 months with his send off of India's Shikhar Dhawan in the fifth match of their one-day series last month.
Nathan Lyon was earlier fined 15 per cent of his match fee for his "ball drop" send-off of AB de Villiers.
Rabada finished with bowling figures of 5-96 while the 21-year-old Lungi Ngidi, who was a surprise pick ahead of Morne Morkel, took 3-51.
Usman Khawaja scored his 11th Test fifty
The animosity between the teams then spilled over in Durban when Australia's David Warner and South Africa's Quinton de Kock were involved in a confrontation on a staircase near the dressing rooms during a break in play. But on the field, South Africa only strengthened their already good position in the second Test in Port Elizabeth, adding 71 runs for the loss of just a single wicket - that of Rabada, the nightwatchman.
Warner called de Kock a "f***ing sook" as they left the field and the new video shows what happened before the two started climbing the stairs. Both received fines and disciplinary sanctions from the International Cricket Council.
"Our stuff is the way we've always played our cricket", he said.
The Proteas are desperate for a win in PE, having lost the first Test in Durban by 118 runs.
The unsavoury development will likely strain relations between the two countries further after a spiteful first Test that saw Warner and de Kock penalised for bringing the game into disrepute. I wouldn't be trying to stop gamesmanship, because that's an important part of the game of cricket, and it's responsible for a lot of the humour in the game. "I have spoken to him a few times about it, to try and get him to relax a bit", pace icon Michael Holding told ESPNcricinfo.More news: Serena Williams defends use of medical exemption at 2015 French Open
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