In pictures: East Fife 1-2 Morton (AET)
The game's flawed ruling on handball forced East Fife to pay the penalty on Saturday afternoon.
With the Fifers closing out a 1-0 home win over Championship side Morton, a cross deep inside the Fife box rattled off the hand of Ross Dunlop from point blank range.
There was absolutely nothing Dunlop could do about the contact, he made no attempt to handle the ball and win any sort of advantage.
Ref Alan Muir, though, decided that contact was enough to penalise the Fifers, despite any intent from Dunlop.
Morton showed no mercy, scoring the penalty which sent the game into extra-time where they would go on to win the tie and advance.
It was cruel on an East Fife side who had been the better of the two across the 90 minutes.
Fife boss Darren Young was livid with the call and, after watching the video back before speaking with the press, believes the matchday ref will realise his error when he too watched the footage.
Young said: “I’ve watched it back and the referee says he (Dunlop) made himself bigger.
“But, once the referee watches it back himself, he’ll soon realise he made a mistake which put us out of the cup.
“We contained them and did very well and I can’t praise the boys enough.
“But decisions can cost games.
“We’ve had maybe seven penalties given against us this season and only one was stonewall.
“You can quite clearly see in the video that Ross Dunlop brings his hands in, it hits his hand and his hand goes back and the ref gives the penalty.
“Alan is a good referee and has a split second to make a decision but it’s cost us.”
The Fifers took a deserved lead shortly before the hour mark when Liam Newton surged brilliantly into the box and squared for Smith to net.
And then came the decision which changed the game, Dunlop cruelly penalised for something he could do nothing about.
Sean McGinty stepped up and crashed his penalty into the top corner before Robbie Muirhead won the tie in extra-time.
The Fifers were out on their feet but could hold their heads high.