Paris Saint-Germain and Istanbul Basaksehir were supposed to face off in the final Matchday of Champions League play in Group H.

Instead, the two sides are refusing to play after the fourth referee allegedly used racial slurs targeted at Istanbul's assistant manager.

Someone on the Istanbul bench was getting a booking in the 14th minute of play. When the match referee asked which coach was meant to receive the card, the fourth referee reportedly said “the Black guy,” per Fabrizio Romano:

What a shame in Paris. 4th ref said “the black guy” when indicating to the ref who should be booked on Istanbul’s bench. Istanbul Basaksehir walks off the pitch for racism. “Why you call him black man?!”, Istanbul players are literally furious.

The video can be seen below. Players from both teams leave the pitch of their own volition in a show of unity and support for Istanbul's assistant manager.

In fact, it was Paris Saint-Germain players like Kylian Mbappe, Presnel Kimpembe, and Neymar Jr. who were among those leading the way off the pitch.

The scene grew very heated in a hurry. Istanbul striker Demba Ba confronted the fourth official after the alleged slur.

https://twitter.com/V1Loxzi/status/1336407110645657609

Unfortunately, this is not the first instance of racial prejudice in European soccer this season. It is also the second time PSG has been involved after Neymar alleged a Marseille defender screamed racial slurs at him during a Ligue 1 game in September.

In any case, this is an ugly scene for soccer and for UEFA, though a strong showing of solidarity from the two clubs involved.