Neil Warnock guided Aberdeen into the Scottish Cup semi-finals in what proved to be his final match as ­manager.

Warnock had faced questions about his future before the game after ­failing to record a win in six Premiership matches to leave Aberdeen third-­bottom of the league.

It turned out his mind was made up regardless of the quarter-final ­outcome. Jamie McGrath’s ­double saw the 75-year-old record a second win in eight matches, having overseen a win over Bonnyrigg Rose in the previous round.

Aberdeen announced soon after the game that Warnock had stepped aside along with his assistant, Ronnie Jepson, having been appointed as interim manager until the end of the season on 5 February.

The Aberdeen chairman, Dave Cormack, said: “With the search for a new manager at an advanced stage, Peter Leven will assume ­control of all first team matters until the process is concluded.”

Warnock said it was the “right time” to leave. “I only came up to help Dave and Alan out and try and steady the ship,” Warnock told BBC Scotland. “Unfortunately we haven’t got the right results in the league.

“They’re well on their way to ­getting a new manager. I’ve been ­telling them they have to push ­forward now. I thought it was the right time.

“We decided in midweek that today was going to be the day. I’m glad I left on a high because the lads were fantastic. I was quite proud of them.”

“I’ve told them they need to get a manager in to look at the squad because I think it needs quite an ­overhaul in the summer. If anything, I’ve contributed to making them ­realise and get a move on.”

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McGrath hit an early opener and rounded off the scoring during a comfortable second half for the home side at Pittodrie.

Graeme Shinnie had put the Dons two ahead and Kilmarnock could not make the most of the lifeline afforded by Danny Armstrong’s strike late in the first half.

Shinnie received a late yellow card for dissent that rules him out of the semi-final.