DEREK McInnes tonight admitted Kilmarnock’s defeat to Inverness Caledonian Thistle in the Scottish Cup quarter-final was a huge blow to the Rugby Park club’s confidence.

The relegation-threatened Ayrshiremen slumped to a 2-1 quarter-final defeat to the second tier Highlanders at the Caledonian Stadium this evening.

They took the lead through Kyle Vassell in the second minute – but conceded a penalty to Billy McKay in the first-half and then Sean Welsh in the second.

McInnes felt that referee David Dickinson was wrong to award Billy Dodds’ men a spot kick after Joe Wright had handled inside his own area because the ball struck his leg first.

But he confessed that Caledonian Thistle had been the superior side and deserved to go through to the semi-final at Hampden.

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“I thought we were second best,” he said. “Inverness wanted it more than us and that is always a sad indictment of a team. It is never easy for a manager to accept that and say it. 

“But the truth of the fact was Inverness were hands-down more energetic than us and had more desire about them. 

“What we have found is when we have lost the first goal on the road we have lost confidence, but that shouldn’t have been the case tonight. 

“The penalty was harsh on us and I thought we could have had one ourselves, but the better team won tonight. The team who deserved it won.” 

Kilmarnock, who were promoted from the Championship last season, are just three points off bottom spot in the Premiership with 10 games remaining.

McInnes acknowledged he would have to lift his charges before their league encounter with St Johnstone at home next Saturday.

"We need to focus on finding a way to win enough points to stay in the league because this is a real blow for us confidence-wise,” he said.

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"The priority is staying in the league and we have work to do to do it.  Our home form is good but the away form is crippling us at the minute.

"So we need to dust ourselves down, find an identity and a way of playing to help us win games.

"Hopefully we can win against St Johnstone next weekend and just focus on the league form."