Paris St Germain and Istanbul Basaksehir players, as well as the three on-field match officials, took a knee before their rescheduled Champions League game restarted.
The match had been suspended on Tuesday when the players walked off in protest after the Turkish club accused a match official of racism.
On the resumption on Wednesday, players also held their fists in the air as they gathered around the centre circle and wore 'No to racism' T-shirts during the warm-up.
UEFA said earlier on Wednesday that it had appointed an Ethics and Disciplinary Inspector to "conduct a disciplinary investigation regarding the incident" on Tuesday.
The incident was sparked when Basaksehir's assistant coach Pierre Webo was shown a red card for protesting against a refereeing decision.
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The Turkish side then alleged that the Romanian fourth official, Sebastian Coltescu, used a racist term towards the Cameroonian.
The four Romanian match officials were replaced by UEFA for Wednesday's resumption.
Taking a knee was popularised by San Francisco 49ers quarterback Colin Kaepernick in 2016 and gained steam as an anti-racism protest following the death of George Floyd, a Black man who died in police custody in Minneapolis in May.
Two banners carrying anti-racism messages were placed in the Auteuil tribune of the Parc des Princes stadium.
The first one read 'Support to Mr Webo... Proud of the players... Against racism', with the second one saying 'Paris united against racism'.
UEFA had two banners of their own with both clubs' logos, reading 'No to racism', one in French and the other in English.
The game, won by PSG 5-1, was played without spectators as part of restrictions in France to contain the spread of the novel coronavirus.
