Rangers caretaker manager Graeme Murty believes predictions of a heavy defeat at the hands of Celtic are all the motivation his players need to inspire them to an upset.Brendan Rodgers’ side are 27 points clear at the top of the league, unbeaten in domestic football and looking for a 23rd consecutive win in the Premiership. That has led some pundits to expect a comfortable home win for Celtic but Murty thinks that talk will sharpen his players’ focus.“It’s easy for me,” he said. “I just show them everything that’s been written about them, how they’ve been written off and Celtic are fantastic and we’re going to get an absolute doing. “You can’t actually control anything about it and it would be a massive waste of energy to be looking at that when I’ve got something fairly large on Sunday to consider,” he said.“[My preparation] doesn’t change. I’m merely here to make sure the players have the detail on Celtic, have the detail on the occasion, make sure we get all of any extraneous detail out of the way and out of their heads so they can go and focus on being excellent on the pitch.“It’s difficult, it’s hard but that’s the job. The job is purely to concentrate on the game.”He added: “We know it’s going to be a difficult game. [A new manager watching] doesn’t make it doubly difficult. The players have been in this situation before. “There’s been no one at the helm apart from me, there’s still been no one appointed so they just have to make sure they concentrate on what we can control. “They can’t control what the weather is going to be like, they can’t control what the surface is going to be like, all we can control is our approach to it and they have to concentrate on putting themselves forward in a very, very good light for this football club.”Murty said his concentration on the game meant he had not given any thought to his part in any future coaching team but expected discussions to take place. “I don’t actually have to motivate them, I just have to say ‘this is what the world thinks about you’. “You can either listen to the noise or be really close together and go and show them what we’re about. Thankfully, you [pundits and the media] have all done my job for me.”Murty is expected to be in the dugout for the last time, with Pedro Caixinha’s appointment as permanent manager imminent. The Portuguese coach is expected to be in the stand watching on Sunday but Murty said the peculiar situation had not been a distraction as he prepared for a “difficult” game.