Celtic and Livingston are "in contact" after an American journalist alleged that Ayo Obileye was subjected to racist abuse by a member of the Parkhead crowd.
Ange Postecoglou's side missed the chance to go top of the Premiership on Saturday as they were held to a 0-0 draw by David Martindale's men.
Greek striker Giorgos Giakoumakis missed a late penalty to win it, but a visiting journalist reported a far more troubling incident.
Philip Crowther, White House correspondent for the Associated Press, is in Glasgow for the COP 26 climate conference.
He attended the match at Celtic Park, posting videos of the crowd singing You'll Never Walk Alone.
The penalty was given after Obileye slapped Kyogo Furuhashi on the back of the head and Crowther alleges that he was called a "monkey" by a Celtic fan.
He later said: "It's important that a football club isn't tarred because of one racist individual within the stadium today!
"When we took the knee at the start of the game we were applauded from all corners and that's the memory I will take away from the game.
"Now it's time to find the culprit."
And Celtic have confirmed that they are in touch with Livingston to look into the alleged incident.
A spokesman said: "We are not aware of any incident.
"However we are already in contact with Livingston, we will treat these reports with the utmost seriousness and they will be investigated thoroughly."
