Nico Raskin appeared to squirt water at an Aberdeen fan at full-time of Rangers' 2-0 win at Pittodrie on Sunday.
The incident happened as the players were walking down the tunnel after the match. The fan then threw an empty cup towards the players as they walked towards the dressing room.
Earlier in the match, Rangers defender Emmanuel Fernandez appeared to be struck by an object from a section of Aberdeen supporters as players celebrated Thelo Aasgaard's opening goal.
Speaking about the incidents in his post-match presser, Rangers boss Danny Röhl said: "I think we want to play football on the pitch. We want to have a friendly atmosphere, but you feel it today, this place here as well, it's tough.
"I think even when I arrived I felt straight away where we are, but we showed the right answer on the pitch, and this is what we want."
Your Site has contacted Rangers for comment regarding the incident involving Raskin.
Speaking on Your Site after the match, Kris Boyd said: "He'll probably be in there regretting it now, but if you're a football player, you're going to get away fans taunting you.
"You just need to go home, you've won the game, you've got three points, difficult venue, get back down the road."
Chris Sutton added: "Vaclav Cerny did it, didn't he, the other year [in match against Celtic in March 2025].
"This is a powder keg of a fixture anyway, this is the last thing it needs. You can't keep going around spraying water on fans, that's an absolute no-no.
"There'll need to be some sort of punishment, otherwise players will just carry on."
Paul Hartley said: "This is a big game, between the two sets of teams and the fans. You've got to be the bigger person and walk away. He might get a punishment now.
"He's an experienced player. Just walk down the tunnel, you've had the win, you've had a good performance, you've got your three points."
Vaclav Cerny - who spent last season on loan at Rangers - was given a formal warning by the Scottish Football Assoication (SFA) after he sprayed Celtic fans with a water bottle as he raced along the touchline to celebrate team-mate Hamza Igamane's 88th-minute winner.
Police Scotland launched a probe into the incident. But the force concluded "no criminality has been established".
