Celtic will play Rangers at Hampden Park in the League Cup final on February 26.
Goals by Daizen Maeda and Giorgos Giakoumakis secured the holders' passage into their second League Cup showpiece in a row under Ange Postecoglou.
On a rain-sodden national stadium, the Hoops finally broke the stubborn resistance of Derek McInnes's Ayrshide side and will meet Michael Beale's men next month after the Light Blues came from behind to defeat Jim Goodwin's Aberdeen in extra-time.
Saturday's semi-final was not without controversy or incident as Celtic saw two goals ruled out by VAR. Japanese duo Reo Hatate and Daizen Maeda were unlucky as their efforts were both chalked off for offside.
Giakoumakis, who has been linked with a move away from the Scottish champions this month, fuelled rumours that he could well stay at Celtic when he shared a cryptic Instagram message posting a snap on Instagram of his celebrations at Hampden, Giakoumakis wrote: "Enjoy every moment like it's your last! On to the final! Thank you for the immense support"
However, it was Kilmarnock who left Mount Florida harbouring a sense of injustice after they felt they were wrongly denied a penalty referee Willie Collum and VAR operative Greg Aitken.
Giakoumakis indeed appeared lucky not to give away a spot-kick. The Greek striker netted the killer second goal to see off Kilmarnock at the national stadium but, moments before his strike, there was a penalty call up the other end.
Despite VAR being called into action when Joe Wright and Giakoumakis hit the deck inside the box, whistler Willie Collum decided not to point to the spot.
McInnes lamented the non-decision afterwards, saying: "We should have. Absolutely we should have. Giakoumakis has got his arms wrapped around Joe Wright and he goes down. He can't get to the ball.
"He has come through the back of him. It is a penalty. I think the referee has a great view of it and I am really disappointed with that. I felt it was a penalty at the time and having seen it again I am even more so."
Join Sean Martin and Tony Haggerty in the video below as they discuss all this and more...
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