FIRST blood to Rangers. This was a real wake-up call for Ange Posetecoglou's side as Celtic were served up an early Scottish Premiership title warning by defending champions Rangers.

The Light Blues ran out 1-0 winners in the first Glasgow derby of the season courtesy of Filip Helander's 66th-minute header.

Derby Day Sunday? It was supposed to be 'Ange Given Sunday'.

Every Celtic fan could have pictured the Postecoglou going full 'Ange Pacino' beforehand in the dressing room and firing his troops up thus...

"You find out life’s this game of inches, so is football. In either game, life or football, the margin for error is so small.

"One half a step too late or too early and you don’t quite make it.

"The inches we need are everywhere around us.

"On this team, we fight for that inch. On this team, we tear ourselves and everyone else around us to pieces for that inch.

"We claw with our fingernails for that inch.

"We know when we add up all those inches that’s gonna make the difference between winning and losing, living and dying.

"In any fight, it’s the guy who's willing to die who's gonna win that inch. That’s what living is, the six inches in front of your face.

"You’ve got to look at the guy next to you, look into his eyes and you are going to see a guy who will go that inch with you.

"You're gonna see a guy who will sacrifice himself for this team, because he knows when it comes down to it you're gonna do the same for him.

"That’s a team, gentlemen, and either we heal, now, as a team, or we will die as individuals. That’s football guys, that’s all it is.

"Now, what are you gonna do?"

All the hype had surrounded the men from Glasgow's east end and their 56-year-old manager who was experiencing his first taste of the Glasgow derby.

Joe Hart, Carl Starfelt, Josip Juranovic, Liel Abada and Kyogo Furuhashi were all making their debuts in the fixture.

It was Celtic and Ange who went into the bearpit of Govan without the backing of any away supporters and in front of 50,000 partisan Rangers supporters.

READ MORE: Celtic player ratings as David Turnbull fails to impress and Josip Juranovic makes debut in loss to Rangers

An enthralling and frenetic first half ended goalless as Odsonne Edouard missed a game-changing sitter.

Ryan Kent shaved the outside of Hart's post and tackles were flying in right, left and centre but only David Turnbull made his way into the referee's notebook for a foul on Connor Goldson.

It was the visitors who enjoy the lions share of possession without really testing Rangers goalkeeper Robby McCrorie in the first half.

Rangers sprang out the traps in the second half and it was no surprise when a thumping Helander header gave them the lead on 66 minutes with Starfelt all at sea.

Kyogo forced McCrorie into two late stops and he probably should have squared for a tap-in for Ryan Christie late on.

Rangers ultimately kept Ange's team at bay and saw the game out reasonably comfortably at 1-0.

Celtic didn't really trouble the Rangers keeper enough, never looked like scoring and did not ask enough questions all afternoon.

Ange's team uncharacteristically lacked any real attacking threat or rhythm in the final third.

It is Celtic who await their first derby win since December 2019 - when they won the League Cup at Hampden Park - and their ​first league victory for almost three years since Odsonne Edouard and Jonny Hayes were on the target in a 2-0 win at Ibrox.

As the dust settles it was Rangers who laid down the early-season marker to Celtic and, rather worryingly, Steven Gerrard's men have now gone six league games without defeat against their rivals.

The Ange Postecoglou fan club may be growing in popularity. The Celtic fans certainly believed before the derby that they could be on the verge of something special with Ange at the helm.

It was legendary Celtic manager Jock Stein who once said “I enjoy being manager here because I like the people who support us".

A first Glasgow derby defeat is an early setback to Celtic no doubt about it. Ange has left Ibrox with nothing and learned the hard way.

Two defeats in their opening four league games is not, at this juncture, title-winning form.

Results against your rivals are also paramount in order to compete for the country's biggest prize.

Ange will also find out that it is only when you beat your Glasgow rivals and make the people who support you happy that you can begin to enjoy being the Celtic manager and everything else that comes with it... inch by inch.