A Benfica fan appeared to throw a stick at Liverpool winger Luis Diaz during the Champions League clash in Lisbon.
And the disgraceful scenes also saw home fans throw projectiles at Scotland captain Andy Robertson as he went to take a corner late in the game.
Former Porto star Diaz lit up the home of his old rivals when he took the ball round keeper Odisseas Vlachomidos to seal the Reds' 3-1 win.
