4 big Celtic vs Rangers VAR calls as John Lundstram bang to rights and ex ref uses old analogy for Matt O'Riley penalty

Former Grade One referee Steve Conroy praised Willie Collum for his Old Firm derby display on a day when there was yet more controversy as Celtic and Rangers went head to head at Parkhead.

There was a huge moment in first half injury time when Collum flashed a yellow card at John Lundstram for a lunge on Alistair Johnston, only to upgrade it to a red after being called to review the incident by VAR Steven MacLean.

Collum was again asked to review a penalty award for the Hoops for a foul by Mohamed Diomande on Matt O'Riley but the whistler stuck to his on-field decision. Conroy was on duty for Record Sport, giving instant reaction to the big calls in our LIVE blog. And he said: "There's no such thing as perfection so I wouldn't have agreed with everything but there wasn't anything big that stuck out that he called drastically wrong so I think he had a good day. "

Conroy also believes Collum could be in line to replace Crawford Allan as the SFA's head of refereeing and might be handed the Scottish Cup final when the Old Firm go head to head again. He said: "There's a growing clamour for it. We're talking about getting someone from abroad or higher profile but we're kidding ourselves on if we think anyone of any great stature will come to us - it's going to be another internal appointment and Willie is the obvious one - the continuity candidate!"

Here, Conroy looks at some of the bid decisions after Celtic's 2-1 win over the Light Blues.

Conroy's verdict: "It was a clear red card. We have been very critical of how VAR has worked of late but that's how it should work. It was a clear and obvious error in my opinion and he was called to the monitor and instantly reversed the decision so fair play to both of them. There is