GRAEME Murty last night apologised to Rangers supporters after his side was thrashed 4-0 by Celtic in the William Hill Scottish Cup semi-final and admitted the humiliating defeat was his lowest moment in football.

Murty, who has only been put in charge of the Ibrox club until the end of the season, refused to discuss his personal future and insisted his side could bounce back and finish second in the Ladbrokes Premiership.

The 43-year-old also stated he will speak to Andy Halliday, who responded furiously to being replaced by Josh Windass six minutes before half-time, about his reaction after he had been substituted this week.

Read more: Matthew Lindsay: Rangers' painful Hampden humiliation was inexcusable - it is hard to see Graeme Murty surviving it 

First-half goals from Tom Rogic and Callum McGregor and second-half penalties from Moussa Dembele, after Ross McCrorie had been red carded for a foul on him, and Olivier Ntcham gave the defending champions a comfortable win.

It was the biggest win Celtic have recorded over Rangers at Hampden since they won the Scottish Cup final by the same scorelined way back in 1969.

Brendan Rodgers’s side will complete an unprecedented double treble if they can overcome Motherwell when they return to Hampden on Saturday, May 19.

Asked what he would say to the Rangers fans who left in their thousands before the final whistle, Murty said: “I would apologise to them for the game. I would ask for the patience and ask them to keep believing, but we can’t keep asking it.

“We have to put a performance worthy of their support. We didn’t do enough to make them want to stay in the stadium today.”

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Asked what he thought the defeat meant for his own position, he said: “I’m not going to talk about my role. I think it would be churlish and selfish to talk about my own situation.”

“We were just passive. I don’t know why. I asked them to get into a shape and the structure was there to allow them to go and press but when it comes to the game, you have to get up closer to your opponent than we did in the first period.”

“I’ll have a look at it. There are things we can all get better at but it’s too raw right now to go into it. We’ll look at it in the cold light of day.”

He added: “There is belief in the squad that they can challenge Celtic, but I didn’t feel it today, not in the first half. I felt it in the last game at home, but that belief keeps getting challenged and we have to step up. It’s our job to make sure this doesn’t have a bearing in the final league games.

“The players need to respond – not just against Celtic. There are big games ahead of us and we have to get a response between now and the end of the season of we want to finish as we should. We all need to have a look at our contributions.

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“Afterwards here was emotion, anger, disappointment – all the things you wuld expect after a game like that It’s about putting all of them into positives to power you through to the end of the season. This is the worst I have ever felt in my career, without a doubt.

“It’s a lonely place standing on the sidelines when that’s going on. I don’t think words are enough to convey how I’m feeling right now.”

Probed about Halliday’s reaction to his substitution, Murty said: “I wouldn’t have been happy. I completely understand his frustration, but I was reacting to a situation in the game and I was looking at a different shape to the team.

“Andy’s frustrated, but I’ll see him in the week and have a chat and take things from there. It’s a frustration thing. If you deal with people in an emotional state, you get an emotional response.”

Read more: Matthew Lindsay: Rangers' painful Hampden humiliation was inexcusable - it is hard to see Graeme Murty surviving it 

Murty continued: “There’s lots of things to look at. I don’t think we got close enough to them. We didn’t put them under enough pressure and allowed them to play through us too easily. All four goals were easily avoidable just through basic, good defending.

“In the second half, we gave them the penalty and sending off which makes their job far, far easier.”

Asked what he had thought of the penalty decisions, Murty said: “It doesn’t really matter what I think of them, does it?”

Murty, whose side drew with Celtic 0-0 at Parkhead back at the end of December, insisted Rangers can close the gap on Celtic in future.

“That’s the million dollar question isn’t it?” he said. “You need really good recruitment, really good tactics and with more passion and belief than we showed today.”