Aberdeen have reported Celtic's Aleksandar Tonev for allegedly racially abusing Shay Logan during their Premiership clash at Parkhead on Saturday.
Press Association Sport understands the Dons defender immediately reported the alleged second-half incident to referee Bobby Madden and skipper Mark Reynolds before informing manager Derek McInnes.
Fourth official Crawford Allan and Celtic were also made aware of the allegation by the Dons management team.
The Scottish FA is awaiting the referee's report which should arrive on Monday.
Celtic were contacted by Press Association Sport but have yet to comment.
Van Gaal: "With additions of Marcos, Angel, Daley and Radamel, we are getting the right balance in the team."
Bayern Munich defender Holger Badstuber faces another lengthy spell on the sidelines after being told he needs an operation on a thigh injury.
The Germany defender, who has only just returned to action after spending 20 months out with a serious knee injury, pulled up after kicking the ball during Bayern's 2-0 win over Stuttgart on Sunday.
Shinji Kagawa admitted it was "difficult to describe" how he was feeling after his fairy-tale return to Borussia Dortmund.
The Japanese midfielder scored on his second debut for the club he re-joined from Manchester United this summer and also played a part in the first goal of a 3-1 win over Freiburg.
– Shinji Kagawa
What I feel right now is difficult to describe.
But it's definitely a feeling of great joy to have been able to play in this stadium again. I had goosebumps.
When the whole South Stand called my name, it was an indescribable feeling.
It was a very warm-hearted welcome. The fans had already welcomed me back and that gave me even more motivation to play well for them, and I think I managed that against Freiburg.
Hull boss Steve Bruce has labelled reports linking him with the Newcastle manager's job as "disrespectful" to current incumbent Alan Pardew.
The pressure cranked up a notch on the under-fire Magpies chief on Saturday as his team were humbled 4-0 by former club Southampton, prompting the 53-year-old to skip the post-match press conference at St Mary's.
– Steve Bruce speaking to FiveLive
It isn't nice - it's a horrible Sunday morning for him and I find it very, very disrespectful that I'm linked with somebody else's job when he's still in a job.
It's a hard enough job we've all got. We all know what it's like now in football management.
That part of the game will never change, but for me at the moment I'm just concentrating on the game against West Ham (on Monday night) and leaving all that aside.