South Africa faced the prospect of being a bowler down for the remainder of the second Test against Australia, after Anrich Nortje limped off with a suspected right groin injury during the opening session of the fourth day in Gqeberha.

Nortje walked off three balls into his fourth over, and it was confirmed by Cricket South Africa at the start of the second session that he would not take the field again for at least the remainder of the first innings.

In Durban, Nortje bowled 40 overs in his first Test (and first-class match) in more than three and a half years. There were questions about whether he could back up with a short turnaround, but he had bowled with impressive pace during training two days out.

On the fourth morning in Gqeberha, he had been part of a sustained barrage by South Africa's quicks, which rattled Australia's top order. He removed Marnus Labuschagne courtesy of a stunning catch at third slip by Simon Harmer, which left Australia 45 for 4.

South Africa played the extra pace bowler in this match compared to Kingsmead, with Kagiso Rabada having returned in place of Keshav Maharaj. They have also played Marco Jansen - who took four wickets before lunch on the fourth day - and allrounder Wiaan Mulder. Harmer is the frontline spinner.

South Africa could have the option of enforcing the follow-on if they bowl out Australia quickly enough, meaning the remaining bowlers would not have a break. Speaking after the third day's play, captain Temba Bavuma had braced his team for two days in the field in their bid to level the series. Before play on Wednesday, he reiterated that approach.

"We obviously like the option of the follow-on, but we'll have to do well," he told Kayo Sports. "[The pitch] hasn't really broken up much, so spin might not be much of a factor as of yet. But I think with that new ball, with the wind as well, there'll definitely be something there for our bowlers."

Nortje is the latest South Africa quick to go down with an injury. Rabada missed the start of the series with a hamstring strain while Lungi Ngidi has also been sidelined. Ottneil Baartman and Kwena Maphaka have hamstring problems. Dane Paterson and Gerald Coetzee are the reserve pace bowlers in the current South Africa squad.