TRUST the process. This manager's not for turning.

It was a simple enough message from Celtic boss Ange Postecoglou to the club faithful ahead of last night's Premier Sports League Cup 3-0 quarter-final victory against Raith Rovers at Parkhead.

Sunday's 1-0 Scottish Premiership defeat against Livingston had brought some criticism the manager's way for the first time this season as Celtic once again failed to win in West Lothian.

That in turn led to some skeletons from their League Cup past being dredged up. 

Famously they were 'dancing in the streets of Raith' after Jimmy Nicholl's Kirkcaldy men had produced a League Cup final shock of epic proportions by downing Tommy Burns' men on penalties at Ibrox back 27 years ago.

The Aussie was having none of that though. ​Success comes with the territory at Celtic. The 56-year-old was hell-bent on securing his first semi-final berth at Hampden Park as well as sticking rigidly to his guns.

READ MORE: Detailed Celtic player ratings as James McCarthy and Jota impress in Raith Rovers cakewalk

One thing is for certain: Postecoglou's footballing style and philosophy are here to stay. 

"I know Sunday's game was probably the most disappointed they've been in our performance," he said. "I've never felt that our supporters were thinking this would be a quick fix.

"We're starting on a road to being a certain type of team and we won't waver from that. I've got confidence in the group and what we're trying to achieve and all these things along the way just challenges to our commitment to it.

"We'll just keep ploughing on in this direction. I don't think there would be any less pressure if we had won everything last year... I think the expectations at this football club are constant, and they should be because that's the history of it."

This is probably why Ange fielded a particularly strong Celtic starting XI against Raith Rovers as Anthony Ralston, Carl Starfelt and Adam Montgomery returned to the side in place of Josip Juranovic, Stephen Welsh and Boli-Bolingoli.

Republic of Ireland midfielder James McCarthy kept his place and he started for the second successive game whilst Celtic fans were hopeful of catching a glimpse of new Greek striker Giorgos Giakoumakis who had signed for £2.5 million on transfer deadline day but had yet to feature.

The 26-year-old striker was the Eredivisie top scorer last season after netting a staggering 26 goals in 30 games for VVV Venlo and was finally deemed worthy of a place on the bench as Celtic entertained John McGlynn's outfit who had claimed Aberdeen's scalp in the last 16 and were flying the flag for the Championship clubs at this stage in the tournament.

Celtic Way:

As it turned out there was to be no debut for Giakoumakis as the manager informed everybody at the end that the forward had injured his calf in the warm-up and had been sent for a scan to assess the damage.

Trust the process? Beware of Greeks bearing goals and all that.

The lights were definitely on in Paradise and Celtic were keen to match the glitzy pre-match disco show and prove that they were indeed at home in more ways than one if they were to recover from Sunday's setback.

A rapid response was required and even this early in the campaign it fell into the must-win category for Postecoglou.

In the four domestic league and cup matches at home so far this season Celtic had bagged 18 goals and they were desperate to add to that tally.

Raith Rovers had obviously done their homework and adapted Livi's template for success as the opening 20 minutes came and gone without a hint of a chance of note for the hosts despite dominating possession.

It was also littered with passages of slack play and resolute defending by the visitors. Sound familiar?

However, the nerves were all but eased on the night after 26 minutes when Jota notched his first goal for the club.

McCarthy threaded a beautifully weighted pass right through the heart of the Raith defence and season-long loan signing from Benfica gleefully slammed it home. It was a superbly crafted goal by Postecoglou's side and lifted the mood considerably in the stands.

Celtic looked Hampden bound on 40 minutes when Liel Abada was on hand to head home following a Jota shot which was palmed away by Raith keeper Jamie MacDonald to make it 2-0.

READ MORE: David Turnbull v Tom Rogic: Which should Celtic boss Ange Postecoglou choose? - James Dailey

It was three and easy on 47 minutes when David Turnbull glided forward and curled a cracker from 20 yards beyond MacDonald's reach on his 50th appearance for the club.

The only surprise was that Celtic did not bag more goals in a one-sided contest.

It was a definite case of job done and a first major domestic cup semi-final and national stadium appearance for Postecoglou as the Hoops booked their place in the semi-final against Callum Davidson's holders St Johnstone which will take place on the weekend of November 20 and 21.

Celtic now remain on course to lift the first of the trophies that they relinquished last season after a four-year monopoly on every piece of domestic silverware.

The home displays may well be in stark contrast to their away form but the victories in Paradise keep coming and the supporters continue to lap them up.

In the public houses up and down the country, the debates will no doubt continue to rage on about the team, manager, squad numbers, results and of course, whether the public limited company are doing and have done all they can to back Postecoglou up until this point.

Criticism is always going to be a part and parcel of football. However, the Celtic supporters are still all in with the Aussie.

They certainly trust the process. They remain 'Dedicated Followers of Ange-ism'.