The former SFA referee believes the defender’s tackle on Zac Sapsford did not meet the threshold for a red card, despite comparisons being drawn with Kai Fotheringham’s dismissal for St Johnstone against Rangers last weekend.

Donovan was booked by referee Steven McLean for the challenge with Celtic trailing 2-1 at Parkhead. VAR Chris Graham reviewed the incident but backed the on-field decision and did not send McLean to the monitor.

Liam Scales later rescued a point for Celtic in the 2-2 draw, keeping them four points clear at the top of the Scottish Premiership.

The Donovan incident sparked debate after Fotheringham had been sent off at Ibrox for a similar-looking challenge on Nico Raskin. On that occasion, Graham was the referee and was advised by VAR Andrew Dallas to review the tackle before showing Fotheringham a red card.

Madden, however, believes neither challenge warranted a sending-off and insists the officials got the Donovan decision right.

Speaking on Instagram, Madden said: “A much-discussed decision from the match between Celtic and Dundee United on Wednesday night, which is absolutely clear in line with the laws of the game and current criteria.

“If you look at the challenge, the Celtic player comes in and clearly plays the ball before he makes contact with the opponent.

“So, let’s look at what the law says. Obviously, this is a genuine attempt for the ball, so it’s not violent conduct, so we need to determine if this is a yellow card offence for recklessness, which is showing a disregard for the opponent, or is it serious foul play and endangering an opponent.

“When considering a red card offence for endangering an opponent, we need to consider: does he play the ball, or is there an opportunity to play the ball? Is there speed, intensity or is there any malice?

“There is speed in the challenge, there is intensity. Is there an opportunity to play the ball? Of course, as the defender plays the ball.

“Is there any malice? There is no extension of the leg even after the challenge, even though there is some contact.”

Madden then pointed to Fotheringham’s red card against Rangers, which he had already argued was the wrong decision.

He added: “When we are considering serious foul play, only last weekend Kai Fotheringham was sent off against Rangers and I was quite clear that it is not a red card, given that point of contact.

“What we need to look at here is consistency of decision-making. If you look at this challenge made by Donovan it does not meet the threshold for a red card.

“Yes, there is speed and intensity but there is not significant enough contact on the opponent to be considered to be endangering the safety of that opponent.

“Red card offences should be absolutely clear. In this situation the referee was correct and the VAR was correct not to intervene.”