Jamie Clarke and Anthony McGill were involved in a feisty exchange at the World Championship, with the referee having to step in to calm the situation.
Scot McGill was unhappy with his Welsh opponent for apparently standing in his line of sight while down on a shot.
Six-time world champion Steve Davis called it a "nasty moment" while 1991 world champion John Parrott said on BBC Two: "I have not seen many [scenes] like that, it is quite heated.
"It is a very small and tight venue when there are two tables and you can get trapped. If you have played your shot and cannot get back to your seat, then as a courtesy you will stay at the other end of the table and hopefully be out of the way.
"If it is continually happening and Anthony feels he is in his eye line then he is perfectly entitled to say something. It does not help being 7-2 down so is not in the best of moods."