Cricket South Africa has issued an apology to Cricket Australia after two CSA officials were photographed posing with fans, who were wearing Sonny Bill Williams masks at St George's Park.

Clive Eksteen, a former left-arm spinner and CSA's head of commercial, and Altaaf Kazi, CSA's head of media and communication, posed for a picture with three fans wearing masks on the first day of the Test. The photo was shared on social media and then picked up by the Sydney Morning Herald , who wrote that the Australian team were "outraged." CSA said it would follow its "normal internal processes," with regards to Eksteen and Kazi, which will likely begin with an internal investigation. They have been asked to return to Johannesburg, where CSA's head office is located.

"On behalf of CSA I extend my sincere apologies to the Board of Cricket Australia, its officials, team management, players and their families," CSA president, Chris Nenzani said.

"Cricket Australia spoke to Cricket South Africa officials yesterday to express disappointment with this matter and events that unfolded off-field Friday at St George's Park," a CA spokesman said. "CA appreciates the swift response, including the sincere apology from CSA, and the seriousness with which the matter is being treated."

The Williams' masks were brought into the ground as an attempt to ridicule David Warner, who was involved in a stairwell spat with Quinton de Kock during the first Test in Durban. Warner was fined 75% of his match fee and earned three demerit points for the incident, later claiming de Kock had made a "vile and disgusting comment," about his wife Candice. De Kock admitted to saying something in a hearing that took place on Wednesday and was fined 25% of his match fee with one demerit point added to his record.

Candice had an encounter with Williams 11 years ago, before she had met Warner and South African fans hoped to use that to antagonise the opening batsman. The day before the Port Elizabeth Test, social media posts, including one by a reporter (who is not working on this game) with the host broadcaster SuperSport shared photographs of fans making Williams' masks and of a songbook with lyrics containing vulgar and derogatory language. While the songs were not heard at St George's Park, the masks were seen but only after CSA officials had to intervene to allow mask-wearing fans into the stadium.

Initially, stadium security had refused to allow them in because of what Kazi called a "misunderstanding," though it is not clear on whose instructions the security were initially acting. Kazi and Eksteen were then contacted by the fans and met them at the gates, where it was decided that they would be allowed in. According to Kazi, the group of fans then asked for a photo with him and Eksteen and the pair obliged.

"We found out because (the spectators) contacted us and we then went to security and got them in. They said 'let's take a photo with you guys," Kazi told SMH.

Speaking to ESPNcricinfo shortly after the story broke last night, Kazi admitted it was "one of the worst judgment calls I have made," and expressed regret over his actions.

Meanwhile, CSA had reiterated that freedom of expression will be respected, within the limits of their own guidelines for spectator behaviour, which does not tolerate any racism, sexism or derogatory comments. A statement read: "While CSA respects the rights of its fans to represent their own points of view, CSA does not associate itself with these actions and urges all Protea supporters from refraining from being involved in distasteful or unwelcome actions that may impact the image of the sport and its supporters."