IN THE FOG of war, clarity is king.

Celtic have had the benefit of receiving no mixed messages from their manager, Ange Postecoglou, for over nine months now – and this part of the campaign is where it pays off.

Occasions such as Sunday’s Glasgow Derby are when he learns how deeply his lessons have been ingrained. This is the way we play – that’s the missive whether it’s a red-hot Ibrox or a freezing cold Dingwall. The answers are in ‘our football’.

It was not a vintage Postecoglou performance – but it was a Postecoglou performance. The playing out from the back, the inverted full-backs, the interchanging wing-play, pressing high. It was all still there, even if they saw a lot less of the ball than usual and at times appeared to struggle out of possession in the midfield areas.

Five minutes in it did seem like maybe a few in green and white hoops had temporarily forgotten what they were all about. That’s where a nod must go to Callum McGregor. The captain, seemingly sensing some around him were overwhelmed by the rapidfire Rangers start, decided he would once again act as the driving force of the team.

Motoring forward with purpose and precision, he caused chaos in the home ranks and scattered the Light Blues rearguard every which way as his actions led directly to Tom Rogic’s sharp equaliser. From then on, Celtic were far more like themselves.

“I think when you have a clear identity like that then even in the most difficult moments you start to gather your thoughts on where the game is and where you want it to be played,” McGregor said afterwards. “We went a goal down but, once we started to calm the game down we started playing ourselves back into it.”

Much of that play was centred round Daizen Maeda’s impressive derby debut – neither James Tavernier nor Calvin Bassey could quite get to grips with him, although Allan McGregor definitely did in a first-half penalty shout that was turned down by referee Willie Collum.

The performance of the two centre-backs was also key. They repelled virtually everything that came their way while combining for the decisive goal; Carl Starfelt once again winning the first ball at an offensive set-piece for Cameron Carter-Vickers to slam home. Tom Rogic’s first half is likewise worthy of commendation while Greg Taylor continued his own solo campaign of silencing his disproportionately vocal critics with yet another stellar display in a big game.

READ MORE: Detailed Celtic player ratings as Daizen Maeda and Cameron Carter-Vickers impress in Ibrox cauldron

Good commanders, it must be said, do adapt to the conditions around them. McGregor alluded to that after the match, too, pointing out sometimes a slight change in your chosen artillery – in this case, using Liel Abada off the bench near the end as it became more about attrition and counter-attacking – is enough to outdo an opponent in the short-term.

“We always want to play good football and play through the lines but sometimes you have to soak up pressure in the game,” he said. “And we have massive weapons in terms of our counter-attack; we've got so much speed in the team, so much quality.”

Of the 11 trips to Ibrox that Celtic had undertaken since December 2016, they had won five and lost six. McGregor would have known better than anyone else – having played in every one of them – that half of those losses had come since the start of last year; it’s not been a happy hunting ground for Celtic in quite a while.

Intriguingly, though, five of the six defeats were 1-0 or 2-0 meaning he’d also know that when Celtic do score at Ibrox, it tends to end in victory. So it proved again here as McGregor helped marshall his men to victory, dealing their rivals a first home league defeat in two years at a crucial juncture in the season in the process. It’s a far cry from their first visit to Govan in August.

“After six games we’d lost three and we were still putting a team together,” the manager said after the game. “But at no stage did I make excuses or any allowances for them. They accepted the challenge ahead of them.”

Ange Postecoglou rarely calls it wrong.

Celtic saw less of the ball. Celtic had fewer shots. Celtic were out-passed. Celtic made fewer tackles. Celtic’s keeper had to make more saves.

Celtic also scored twice. Celtic moved six points clear at the top of the league.

The whys and wherefores of how one battle was won do not particularly matter when victory in the war has been brought so much closer as a result of it. Six points, six games. No excuses.