IT is the 90 minutes that will make or break Rangers’ campaign. And, it seems, Graeme Murty’s Ibrox ambitions.

Victory over Celtic this weekend would put the Light Blues within touching distance of major silverware once again and give their manager a chance of remaining at the helm next term.

But the consequences of defeat are severe for both. Not only would a Hampden heartache give the Gers’ Old Firm rivals a chance to claim successive Trebles, but it would surely all-but end Murty’s hopes of being boss beyond the summer.

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The targets for the 43-year-old were clear when he was handed a contract until the end of the campaign. Second place in the Premiership had to be secured, and the Scottish Cup had to be won.

Both of those goals can still be achieved. For the sake of Rangers and Murty, that must still be the case come Sunday evening.

But former Light Blues boss Ally McCoist believes it would be wrong to judge Murty on just one afternoon of Old Firm drama. The derby snapshot could overshadow the bigger picture, however.

“The feeling seems to be that it’s a defining game, and that’s not necessarily correct in my opinion,” McCoist said.

“I think you have to take a step back and look at it, Celtic are the best team in the country at present. A lot of people would expect them to win the game regardless.

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“It’s probably true that if Graeme manages to win he stands a better chance of getting the job. But it would be wrong, in my opinion, to judge the man over one game.

“Any fair minded person would look at his overall performance which I think has been good. Over the piece I think he’s done a good job.

“His signing have been good, there have certainly been an improvement in terms of performances although, at Rangers, you are only ever one game away from a crisis.

“Losing to Celtic, losing to Kilmarnock was not ideal. But it shouldn’t be as simple as to say that because of that he doesn’t get the job.”

Murty has repeatedly stressed that he is content to work to the original timescale and discover his future at the end of the campaign.

In an address to supporters on Monday, chairman Dave King thanked Murty for his efforts in recent months after he was thrust back into the spotlight following Derek McInnes’ decision to reject the chance to replace Pedro Caixinha.

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But he also targeted ‘immediate success’ as he vowed to help bring silverware back to Ibrox following another tumultuous campaign.

McCoist said: “I don’t think a decision has been made. It would be extremely difficult to keep it quiet if one had been made.

“Dave King will let everyone know when the time is right what the plans to move forward will be.

“The timing was perhaps a little bit strange but he hasn’t said Graeme isn’t getting the job.

“A lot of people are surmising. His comments are correct.

“The next appointment is absolutely vital but that’s not to say it won’t be Graeme. People are jumping to conclusions.

“It’s difficult for me to say whether he’s done enough because I don’t know what the options are.

“Dave King and the board can answer that. What I would say is that I don’t think Graeme has done his chances any harm at all.

“I’ve heard the rumours about Frank de Boer, Derek McInnes has been mentioned again as has Alan Pardew. I don’t know what the board are thinking.”

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Rangers went into the last Old Firm clash at Ibrox on the back of their longest winning run since they returned to the Premiership.

And supporters had dared to dream about a potential challenge for the silverware after closing the gap to Brendan Rodgers’ side.

While Celtic have their sights set on another clean sweep this term, there is plenty up for grabs for Rangers as the countdown continues to Sunday’s showdown.

McCoist said: “I wouldn’t say there is more at stake for Celtic. It is a vital game for both teams.

“It is a bit strange because that run has been there because there has probably been a gulf between the sides.

“When I go back to when Rangers were the better team – or before that when I first signed and Celtic were the better team – there was never any chance of that happening. Because the opposition boys would lift their game and the underdog would come back.

“There are a lot of reasons for that. The game has changed and you can’t show as much passion in tackles and so on. It is one of the reasons why the better team now will dominate, because the physicality has been taken out of the game a little bit.

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“There is clearly pressure on Celtic as well because back-to-back Trebles is an incredible achievement.

“You can talk about standards and where Rangers have been but, to be fair to them, Celtic didn’t achieve it when Rangers were down in the third or second tier because Kilmarnocks and Invernesses and other clubs were winning cups.

“They have to be given enormous credit for having an opportunity to do it. They will win the league. For Aberdeen, Motherwell and Rangers, the chance to stop them is in the Scottish Cup.

“So there is a degree of pressure on Celtic but, at the same time, I would far rather have that pressure than the other pressure.”