A glass bottle was thrown on to the pitch as Bayer Leverkusen celebrated their third goal in the Europa League clash at Ibrox.
Striker Leon Bailey could be seen picking up the bottle close to the corner flag after netting late on in his side's 3-1 victory.
A number of Rangers fans have taken to social media to condemn the person responsible and UEFA are likely to look in to the incident themselves.
Rangers suffered defeat on what was a tough night for Steven Gerrard's side.
They went behind in the first half through a Kai Havertz penalty before Charles Aranguiz made it two after the break.
George Edmundson got one back before Bailey curled the ball past Allan McGregor to seal the victory late on.
Rangers now have a tough task to overturn the deficit when they travel to Germany next week.
