All strikers will be familiar with that piercing whistle.
When a referee has given a corner that, after a few seconds of reflection, he realises should have been a goal kick but cannot be seen to have committed the cardinal sin of changing his mind, so instead opts for the restitutio in integrem of picking out a phantom foul in the penalty-box jostle.
No doubt Sam Cosgrove has heard that whistle plenty already in his relatively short career.
So in some respects it was quick thinking from the Dons striker to hit the deck with Alan Muir still seemingly chewing over the borderline handball which he had decided against penalising seconds earlier, and afford the official a second chance to point to the spot.
In the end the conclusion was right, albeit by the accumulation of two wrongs.
Whatever Shaun Rooney may have done to Cosgrove it did not reach the standard of what is generally understood in practice to be a foul, but the blocking of Andy Considine’s original shot by Callum Booth’s elbow was, according to the current laws, illegal.
It is nonsense that it should be considered so, but those are the conditions under which the game today is being played.
— Aberdeen FC (@AberdeenFC) December 27, 2020
But if Muir thought the two decisions would cancel out with no net effect, it proved otherwise.
St Johnstone appeared to lose their composure along with their lead, and never recovered either.
One can sympathise: the magnitude of their fury over the award given would naturally be greater than that of any relief at escaping with an offence which nobody outside of IFAB thinks should be.
The polar shift in mindset effected in that moment allowed Aberdeen to gain the upper hand in a match meandering away from them, their powerful start to the second half rubbing in the necessary salt to make the wound unsalvable.