David Ospina's blunder on the goal-line as Arsenal fell to Olympiakos last week has probably gone a long way in deciding whether the Gunners can qualify from their Champions League group this season.

But it has had another farther reaching consequence as UEFA referees chief Pierluigi Collina has revealed.

The former elite official says goal-line officials (or fifth officials as we know them as) can make non-verbal signals after the Dutch official Danny Makkelie used his arm to signal that a goal should be awarded against Arsenal as goalkeeper Ospina dropped the ball over his goal-line.

Previously, fifth officials were only allowed to make verbal communications to the main referee.