Willie Collum says VAR was right to intervene and overturn Celtic's penalty against St Johnstone last weekend.
Brendan Rodgers' men ran riot at Hampden as they booked their place in next month's Scottish Cup final.
Callum McGregor, Daizen Maeda, Adam Idah, and Jota all scored in a rampant 5-0 victory.
Read more:
-
I flopped at Celtic after £3.75m move - historic La Liga side now want me
-
Dundee United vs Celtic: TV channel, live stream & kick-off time for title decider
Celtic were 4-0 up at the break but didn't let up in the second 45. Just before he was withdrawn on 64 minutes, James Forrest looked to weave his way through the opposition defence.
He was eventually brought to ground as he did so, and referee Calum Scott initially pointed to the spot.
After co-operation with VAR, however, he changed his decision.
The SFA's Head of Refereeing, Collum, recently spoke out on the incident: "So there is an initial challenge outside the box, but as they come into the box, the first challenge is what the referee initially awards the penalty for," he said [VAR Review Show].
"Watching the footage live in the VAR centre, it looked like a penalty kick, but when you start to analyse the challenge the referee has punished, there is no contact or minimal contact.
"There has been talk about an arm coming across [the face of Forrest] - that's not enough in terms of a threshold for us to award a penalty kick here.
"This is a correct intervention."
Celtic are back in league action this afternoon as they travel to face Dundee United at Tannadice. Avoid defeat, and Rodgers' men will be crowned champions of Scotland for the fourth consecutive season.
