Vernon Philander concedes Kagiso Rabada would leave "a big hole" if he is suspended as a result of his emphatic send-off towards Steve Smith on day one of the second Test between South Africa and Australia.

Rabada was Australia's tormentor-in-chief as his 5-96 saw the tourists, who lead the four-match series 1-0, restricted to 243 all out, with South Africa closing on 39-1 in reply in Port Elizabeth.

However, it was Rabada's dismissal of Australia captain Smith that may land him in hot water with the ICC, as the Proteas paceman gave a screaming send-off and made contact with his opponent's shoulder.

With Rabada having already accrued five demerit points and previously been banned for one Test, he is potentially one misdemeanour away from a two-Test sanction.

And Philander recognised the void Rabada could leave, saying: "I don't even recall there being a send-off.

"We are probably allowed to celebrate sometimes.

"Sometimes there is a fine line whether to celebrate too hard. It's all up to the umpires and the ICC match officials to make that call.

"Sometimes there is going to be a little chirp.

"He would leave a massive hole, he's a big part of this bowling line up. Let's hope that's not the case."

The incident follows a fractious first Test that saw David Warner and Quinton de Kock charged by the ICC for a confrontation on the stairs in Durban, while Nathan Lyon was fined for his "drop ball" send-off to AB de Villiers.

"After the last game it was always going to be sensitive‚" Philander added. "The umpires were always going to try and be in the game and try and find out what's going on.

"But they're within their rights to try and kill some bug or virus from spreading too quickly."