Allan McGregor slaughtered the standard of refereeing in Scotland as he called out a "mind-boggling" decision in the Scottish Cup final.

The former Rangers goalkeeper was left furious after Dujon Sterling received no free-kick from Nick Walsh after being bundled over by Liam Scales at Hampden.

The Celtic defender appeared to push Sterling over during the first half, leaving McGregor irritated but unsurprised as he launched a scathing review on the officials.

McGregor - on punditry duty with Premier Sports - called out the "state of these referees" as he hammered the decision.

In a savage verdict, McGregor commented: "It's mind-boggling. It doesn't surprise me with the state of these referees to be fair. 

"And the the linesman...oh I'm on one...is 15 yards away, what is he looking at? 

"I don't understand it but it doesn't surprise me from these to be fair."

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The Ibrox hero was in agreement, however, with Walsh's decision not to award a penalty for an alleged handball by Ben Davies.

A Kyogo flick in the box saw the ball deflect off the Rangers defender's arm but Walsh did not point to the spot - with John Beaton not calling for any pitchside review.

The former Ibrox goalkeeper said: "We have seen probably worse ones given than that. But it is the rule, and probably a subjective rule as well so you are going to get ones that are worse than that, you are going to get ones exactly like that which are given.

"I don't like it to be perfectly honest with you."