There hasn’t been much that Ange Postecoglou has got wrong since he came to Celtic, but it could certainly be argued that he got away with a rare misstep in his team selection against Rangers at Ibrox.

There were eyebrows raised when the Celtic manager named the likes of Alistair Johnston, James Forrest and even Matt O’Riley over the in-form Aaron Mooy in his team for the trip across Glasgow. Perhaps only Johnston vindicated his selection as he was thrown in for his debut against Rangers at right-back despite the presence of Josip Juranovic on the bench.

“I thought he was good,” said Postecoglou.

“It’s a difficult game to throw him into. Not only is it a derby, it’s away from home and also we all knew it was a big game for a number of reasons.

“For the most part, he handled himself really well. He was solid defensively. He was up against a very good player in Ryan Kent.

“There is more to come from him, especially in an attacking sense once he gets to understand our game.

“He won’t get a sterner test than that as a Celtic player. He came through it really well.”

O’Riley has been a tremendous signing for Celtic since his arrival at the club from MK Dons a year ago, but the relentless schedule seems to have been catching up with the 22-year-old in his last few appearances.

He has yet to score in a competitive game this season, and with Mooy bagging a double in the emphatic win over Hibernian last midweek, the Australian may have considered himself unlucky not to have started the game here.

READ MORE: How Celtic rated as champions dug deep to maintain lead over Rangers

It may have been easy to see the reasoning in including Forrest in the line-up for his experience, particularly on the right ahead of the inexperience of Johnston at the other end of the scale on his debut, but it appeared even more logical to include Liel Abada instead, who has had so much joy of late drifting in on the blind side of Borna Barisic in this fixture.

Both of those switches were made later in the game, and Celtic steadied what had become a listing ship midway through the second period as a result.

All that being said, and staying on the topic of substitutions, it could also be argued that Postecoglou got another big early call wrong when he opted to call on Juranovic to replace the injured Greg Taylor, despite having a natural left-back (and a £3.75m one at that) available in the shape of Alexandro Bernabei.

That may say something about Postecoglou’s level of trust in the Argentinian at this point of his admittedly fledgling Celtic career, but the imbalance it caused in the Celtic team was a major factor in the control they had established in the game during the opening 25 minutes or so slipping away.

Another cause of that momentum shift was the dalliance from Joe Hart that almost allowed Rangers to level as his clearance struck Alfredo Morelos. The keeper may have redeemed himself in the moment by tipping Ryan Kent’s subsequent effort onto the post, but it acted as a rallying cry for a home support who to that point had been as uncharacteristically meek as their team had been.

Still, even Postecoglou admitted that the decision to put his Croatian right-back over on the left had been a detrimental one for his team, putting their ‘balance out of whack’.

It also didn’t help that on an individual level, Juranovic had an absolute – albeit rare – stinker of a performance on his first appearance since the World Cup. His use of the ball was poor, and he was given a torrid time by the pace and direct running of Fashion Sakala.

READ MORE: Ange Postecoglou snaps back over Celtic frustration question

Given the speculation surrounding Juranovic at the moment, there may be a fair chance that will be the last we see of him in a Celtic jersey, but it is almost a certainty it will be the last we see of him playing at right-back in an Old Firm game.

If an off-day for Juranovic is rare, then an off-day for Postecoglou comes into the hen’s teeth category, and even on an afternoon where he did make mistakes, credit is still due to the Celtic manager on two scores.

Number one, in the way he went for broke with his substitutions late on, keeping Kyogo on the field despite the introduction of Giorgos Giakoumakis.

“We needed goals,” Postecoglou explained. “Kyogo’s pretty clever. He can drop in as a 10, he has played that in his career. So, I just felt at that time that we needed a goal.

“Rangers started to retreat a bit which meant that hopefully we would get more balls in the box. And if we did that, having extra bodies in there would help us. It worked out that way.”

Secondly, the Celtic manager must be praised for the never-say-die attitude he has instilled in his team.

The relentlessness that has become a trademark of his side - even when they are below par - proved pivotal, as they eventually caused some chaos in the Rangers box in the dying embers of the game and Kyogo popped up to salvage a draw from the jaws of defeat.

“Even in our comfortable victories, you’ll still see us being really aggressive until the last minute,” he said.

“The players are conditioned to think that way and play that way.

“It’s easy for me to talk about it, but in today’s environment, and the way the game was, it would have been almost natural to say ‘jeez, it’s not going to be our day’.

“But this group of players just doesn’t do that.”