But Worrall produced a close-range finish four minutes into the second half to rescue Rangers and the bitter rivals are now set for a sixth meeting this term when they do it all over again at Ibrox a week on Tuesday.

The on-loan Nottingham Forest defender – whose strike was his first since making Ibrox switch – said: "It's a massive goal. The gaffer said at half-time we needed a goal to save our season and stay in the cup.

"Aberdeen is a tough place to come and they are a physical side but they have to come to our place now.

"I'm just happy we're still in the cup and whoever got on the scoresheet didn't matter.

"It is important we stay in this cup as long as we can and keep picking up wins and keep the momentum going."

Cosgrove, who will miss the replay after picking up his second booking of the competition, got his chance nine minutes in when Connor Goldson wiped out Gary-Mackay Steven inside the box.

But the Aberdeen scorer played a part in Worrall's equaliser as he let the Gers stopper go free to score from a Ryan Kent corner after bumping into team-mate Lewis Ferguson.

Both sides had chances to snatch a place in Monday's draw for the last four as the second half wore on but Gerrard believed a draw was merited.

"Aberdeen edged the first 45 minutes but we were better in the second half," Gerrard said.

"There was only the penalty between us and I asked the players for more in the second half and to be braver on the ball.

"Both teams could have won the tie. Allan McGregor made a save and Scott McKenna made a game-saving block from Alfredo Morelos. (Andrew) Considine was lucky not to give away a penalty too for handball but all-in-all a draw was a fair result."

Mackay-Steven was taken to hospital after limping off after the penalty incident, but Reds boss Derek McInnes is confident the damage is not serious.

And having tasted victory against the Light Blues in Glasgow twice this season already – the first at Hampden in the Betfred Cup semi-finals before a December league clash at Ibrox – he insists Aberdeen have nothing to fear in the replay.

McInnes said: "Gary is away to the hospital for an x-ray as a precaution. We feel it is a bruise on the calf and hopefully it'll heal in a few days.

"We're disappointed not to win from a winning position but there was plenty of effort.

"We have to do it all over again and it doesn't matter to me that we have to go Glasgow. We've won there already this season and our away record is very good. We'll be alive and kicking for the replay."

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