Former Celtic defender Mark Wilson has questioned what Willie Collum was thinking on VAR during the recent derby against Rangers.

An incident in the first half caused controversy as Collum did not feel that referee Nick Walsh had made a clear and obvious error by failing to award the Ibrox side a penalty following a handball by Hoops defender Alistair Johnston.

Collum believed that Walsh had been correct just to give a goal kick because he felt the Celtic player's hand was in a natural position when it made contact with the ball after watching a replay back at Clydesdale House.

Television footage later showed that Rangers forward Abdallah Sima had been in an offside position when John Lundstram played the ball in to him.

But Walsh did not indicate that was the reason why the penalty was disallowed at the time and the goal kick was then taken by Celtic goalkeeper Joe Hart.

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And Wilson made his feelings clear on the situation. Speaking to Sky Sports, he said: "I do not know how much that is going to clear things up when they get the audio but I can sense the frustration.

"At the time, I do not think there would be many people that would disagree with it being a penalty.

"Alistair Johnston gets himself in a whole load of trouble there and he definitely handball's it.

"What followed was interesting as the game restarted with a goal kick, however, when the lines were drawn later it on it was certainly offside.

"So the penalty would not be given anyway but I am just wondering what Willie Collum was thinking on VAR at the time not to look at that or signal that it was offside.

"Did Willie Collum just think it was not a penalty? I would be astonished if that was the case but I am not to sure if that will come through in the audio.

"Rangers may have to wait patiently to get that."