THERE are certain non-negotiables if you want to play for Celtic, and those count doubly if you want to win a Premiership title. You must be relentless in your pursuit of success, and you must be resilient when that success looks to be slipping away.

Celtic have shown both of those qualities this season, and their manager Ange Postecoglou saw plenty of evidence of that as his team dug out the draw they needed against Rangers to inch themselves closer to a remarkable title triumph.

Postecoglou said beforehand that he would never send his team out to play for a draw, but by the end of a hugely testing second half against Rangers, he was more than happy to settle for one.

The Ibrox side threw the kitchen sink, the dishwasher and the tumble dryer at their opponents as they desperately tried to cling onto their Premiership trophy by their fingernails.

Celtic managed to prise them off in the end though not by blowing their opponents off the pitch as they did here in February, but by showing the strength of character that has consistently come to the surface whenever their easy-on-the-eye football has deserted them.

Physically, Postecoglou admits that the season may be taking a toll on some of his players at last. But mentally, he simply can’t fault them.

“To a certain extent [some may be feeling tired],” Postecoglou said. “For them, Matty (O’Riley) is 21 years old and for Reo (Hatate) this is his first sort of journey outside his own country and it has new challenges.

“I have said all along that there is a relentlessness when you play for this football club and you can’t rest on what you did last week or even the last pass or the last action, it’s constant and it’s always there.

“But you are never going to build that into players if you shield them away from it. This year my thoughts were just to expose as many or our players to it as I could. Earlier in the year we were throwing guys in without even training and the expectations are still there, you have to perform.

“We will learn from it. I said to the players after the game, we have so much more growth to do as a football team. But you can’t question their character.

“Even when things aren’t going well they have found a way to hang in there, they have found a way to find that moment or that resilience to get the job done. To me that’s a lot harder to find than improving them in aspects them of their play.

“We had a big challenge today. Okay we didn’t win the game but we didn’t lose it either. That was always going to be the key for us. We haven’t lost for a very long time in the league.

“This group has always embraced every challenge without fear or favour. We haven’t shirked away from the fact that our goal was to be champions this year and we are in a great position to do that. “Our job now is to finish it off and make sure we finish the season strongly.”

Postecoglou felt that his team should have avoided the nervy ending to the match that materialised, missing some gilt-edged opportunities to move further ahead after going in front.

Chief sinner was forward Daizen Maeda, who missed two wonderful opportunities after doing brilliantly to set up Jota for the opener, but just as he didn’t want to be too harsh on the Japanese attacker, Postecoglou was also prepared to cut his team as a whole little slack.

“It was a great goal we scored, I thought Daizen was outstanding,” he said.

“We had two or three really good opportunities after that and normally we would be pretty efficient with the shooting.

“I keep reflecting on the fact this group has been put together in the last eight or nine months and for a lot of them it’s their first real year of expectation and pressure.

“You only gain experience by being out there and going through it and I thought at times we were just a little bit tense [on Sunday].

“Again I think that’s because, for the most part they are a young group – even in terms of average age.

“I always temper my analysis with an understanding of where we are at as a group in the first year of being together playing against a team that’s been together for three years and were champions last year. They’re a good side.”

The nature of the result yesterday meant that while Celtic were certainly content with the outcome, the title party champagne had to be placed on ice for just a little bit longer at least.

When the corks are finally sent flying – perhaps next week with a win over Hearts – Postecoglou thinks it will taste all the sweeter given the challenges his squad have been forced to overcome.

“The boys are not jubilant,” he said. “They understand that they had to work hard [yesterday] to get something out of it. We will keep improving as a football team but the character they are showing at the moment, that’s priceless.

“That’s what is going to hold us in good stead not just for this year but for years to come if we keep having that mentality of taking on every challenge before us and making sure we don’t yield and we don’t give up at any stage.

“I think they are a determined lot and they are determined to finish the season strongly.”