Willie Collum has given his verdict on the two Celtic goals disallowed for offside during the win over St Mirren.
The champions won 2-1 in Paisley but it could have been more comfortable if both Camilo Duran and Shim Mheuka had not had goals ruled out.
Supporters were miffed at both decisions as they pored over the replays. For Duran's, they weren't convinced the lines had been drawn at the correct point of when Yang played the ball to his teammate.
However, Collum was satisfied with it.
He said: "Yes, we are really happy with this decision, Gordon. This is textbook for us in terms of the VAR protocol.
"The VAR team are very, very thorough in going through the process and correctly identifying the correct kick point. That is really, really important. They use another camera here to make sure they get the accurate point at which the Celtic attacker plays the ball, and then they draw the lines.
"They are also very careful to make sure they have drawn the lines on the correct defender. They check the St Mirren player closest to the Celtic goalscorer, and the Celtic player is just marginally offside.
"This is a correct process, absolutely textbook. The calmness, the composure and the communication between the VAR and the on-field officials is really, really good for us. This is a correct outcome."
On the identification of the 'kick point' he agreed that viewers at home have to be mindful that the VAR operators know how the technology works
He added: "Yes. Once you identify the kick point, you know the other cameras are all in time with that, and you can see when the offside is."
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For the Mheuka decision, lines couldn't be drawn on defender Alex Gogic because the two players were so close together. The VAR officials were convinced they could tell Mheuka was advanced of the Cypriot, and the referee agreed after being sent to the monitor.
Collum said: "Firstly, I’ve heard people saying the lines malfunctioned. They never malfunction.
"You can still draw lines here, but if you attempt to draw lines on Gogic, you’ll be guessing. As we said in the first clip, we don’t guess.
"What happens here is that, when the VAR officials are analysing it, they use a variety of angles, Gordon. In their opinion, the Celtic player is offside.
"If they think the player is onside, or we think there is serious doubt about it, they don’t bring the referee to the monitor. But here, in their opinion, the Celtic player is offside.
"I think the majority of people looking at that would agree that the image looks like the Celtic player is offside."
Asked if 'looks offside' is enough, he added: "Yes, it is. If you don’t bring the referee to the monitor here, you are either checking and completing a decision that you think is incorrect simply because you are unable to draw lines on the defender.
"The referee is brought to the monitor, and it is then up to him to make that decision. It doesn’t become a factual overturn because we don’t have the lines there to put down and say this is factually offside.
"We leave it to the on-field match official to assess it. We are not guessing this decision in this particular situation."
