The Hoops forwards often found themselves being grappled and held by the Bianconeri defenders at set-piece plays and Commons believes there were certain calls for penalties which were not awarded by Spanish referee Alberto Undiano Mallenco and his team.
"Gary Hooper was pulled down to the ground on far too many occasions and we got no rewards," said Commons.
"You've got a referee there, a guy behind the goal, a linesman - the whole idea of the official behind the goal is to look out for this sort of stuff.
"If he can't identify when people are being hauled, manhandled, wrestled to the floor then I don't think he should be in a job.
"He's 10 or 15 yards away and if it was a clear foul it should've been a penalty.
"When we had this whole prep talk about the officials being in this area, this is the things they were pointing out and looking for - shirt-pulling and manhandling."