The SPFL has urged Rangers fans to contact the police to ensure the individual who hit Arne Engels with a coin at Ibrox is brought to justice.
Celtic midfielder Engels needed treatment on the pitch after receiving a missile late in the game while preparing to take a corner, but was able to continue playing.
The league has joined both clubs in condemning the incident which took place on the corner of Broomloan and Govan Stands during Thursday's match.
“This behavior is completely unacceptable and we fully support any measures taken to identify those responsible for such stupid and criminal acts,” reads a statement from the SPFL.
“The dangers of so-called fans throwing such objects onto the pitch are obvious and anyone found guilty of such disgraceful conduct should be dealt with severely by the courts, including the imposition of football banning orders.
“We await the match delegate's report and urge any fans with relevant information to contact Police Scotland.”
Policeman puts coin thrown at Celtic's Arne Engels in evidence bag
Celtic manager Brendan Rodgers said Arne Engels was almost hit in the eye.
Rangers condemned “in the strongest possible terms” the incident which occurred towards the end of a 3-0 win for the home team and said they will assist police with their investigation.
There were no Celtic fans inside Ibrox due to the ongoing dispute between the Glasgow clubs over the allocation of away tickets.
Celtic said they believe police are investigating two separate incidents, with the other involving a missile fired at manager Brendan Rodgers.
“The repeated missile attacks against our players and staff are quite appalling and completely unacceptable,” a club spokesperson said.
Rodgers confirmed that Engels was “fine,” but added that “an inch lower and he would have been hit right in the eye.”
Celtic right-back Alistair Johnston saw Engels hit and warned fans to “be smart” at games.
“There are humans out there, someone's son, so let's refrain from throwing things at their heads,” the Canadian said.
Match referee Don Robertson was seen handing the coin that hit Engels to the fourth official. He was then handed over to a police officer, who placed him in an evidence bag.