Wicketkeeper Quinton de Kock made himself unavailable for South Africa's T20 World Cup match against West Indies after refusing to take the knee.
Cricket South Africa (CSA) issued a directive before the match that all players should make the gesture.
Captain Temba Bavuma said at the toss in Dubai that De Kock, 28, withdrew "for personal reasons".
CSA said later on Tuesday that they "noted the personal decision" of De Kock to not take the knee.
In a statement released during the game, CSA said it would "await a further report from team management before deciding on next steps".
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De Kock has previously declined to take a knee.
He said in June: "My reason? I'll keep it to myself. It's my own, personal opinion.
"It's everyone's decision; no-one's forced to do anything, not in life. That's the way I see things."
The CSA statement read: "All players are expected to follow this directive for the remaining games of the World Cup.
"After considering all relevant issues, including the freedom of choice of players, the board had made it clear it was imperative for the team to be seen taking a stand against racism, especially given SA's history."
CSA said in November that players had three options to show their support for social equality: kneeling, raising a fist or standing to attention.
De Kock stood with his hands behind his back during the show of solidarity during the limited-overs series against West Indies in July.
Some South Africa players - but not all - took the knee before the defeat by Australia in their T20 World Cup opener Saturday, when De Kock scored seven.
CSA said on Tuesday that it was important for the team to take "a united and consistent stand against racism".
"Concerns were raised that the different postures taken by team members in support of the BLM initiative created an unintended perception of disparity or lack of support for the initiative," the statement read.
"CSA believes success both on the field and beyond the boundary will be guaranteed if all South Africans stand united to build a new innings based on the pillars of inclusivity, access and excellence."
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