South Africa's Quinton de Kock opted out of Tuesday's T20 World Cup game against West Indies as he refused to take the knee.
Cricket South Africa (CSA) initially revealed De Kock was unavailable for South Africa's Group 1 match at Dubai International Stadium for "personal reasons".
That came after the CSA board on Monday came to an agreement that all Proteas should take the knee before their remaining World Cup games, as a consistent and united stance against racism.
Some players had not taken the knee prior to the loss to Australia on Saturday, and wicketkeeper-batsman De Kock has previously declined to make the gesture.
CSA has now confirmed former captain De Kock refused to go along with the order.
A CSA statement said: "Cricket South Africa has noted the personal decision by South African wicketkeeper Quinton de Kock not to take the knee ahead of Tuesday's game against the West Indies.
"All players had been required, in line with a directive of the CSA board on Monday evening, to take the knee in a united and consistent stance against racism
"This is also the global gesture against racism that has been adopted by sportspeople across sporting codes because they recognise the power of sport to bring people together.
"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.
"The board's view was that while diversity can and should find expression in many facets of daily lives, this did not apply when it came to taking a stand against racism. The board will await a further report from team management before deciding on the next steps.
"All players are expected to follow this directive for the remaining games of the World Cup. CSA thanks all other Proteas players for agreeing to unite and make such an important public stand against racism."
Cricket South Africa (CSA) has noted the personal decision by South African wicketkeeper Quinton de Kock not to “take the knee” ahead of Tuesday’s game against the West Indies.— Cricket South Africa (@OfficialCSA) October 26, 2021
Full statement: https://t.co/cmEiA9JZy7 pic.twitter.com/4vOqkXz0DX
CSA board chair Lawson Naidoo earlier stated: "A commitment to overcoming racism is the glue that should unite, bind and strengthen us.
"Race should not be manipulated to amplify our weaknesses. Diversity can and should find expression in many facets of our daily lives, but not when it comes to taking a stand against racism."