A WORK in progress.

Four words that have defined the new look Celtic under Ange Postecoglou thus far.

It's all about the bigger picture now.

The Australian slotted in another vital piece of his team jigsaw before kick-off against St Mirren at Celtic Park today as the club announced the capture of Croatia international Josip Juranovic on a five-year £2.6 million deal from Legia Warsaw subject to international clearance.

The 26-year-old right-back has amassed 10 caps for his country and featured against Scotland and Spain during their run to the last 16 at this summers European Championships tournament and will join the rest of the squad early next week.

The signing provides much-needed depth in the right full-back position with only Anthony Ralston currently on the club's books.

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As Ange himself said: "We are absolutely delighted to be bringing Josip to the Club and we are sure he will be a great addition to the squad and will add important quality and depth.

"Everyone at the club has been working hard to add to our squad and we have made good progress."

There is a feel-good factor coursing right through Celtic at this juncture.

Securing a player in what has been considered a problem position for Celtic for quite some time is another short-term coup for Ange.

He is winning friends and influencing the people that matter most off the field whilst helping build some incredible momentum on it.

Today's Premiership outing against the men from Paisley was a case in point.

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Aussie midfielder Tom Rogic and winger James Forrest were rotated and left out against the Saints after both featured in the starting eleven during Wednesday's 2-0 Europa League play-off round first-leg win over AZ Alkmaar.

Rogic had to be content with a place on the bench whilst Forrest didn't even make the bench as Odsonne Edouard and Ryan Christie returned to the fold.

That did not deter the men in green and white.

The crowd in Glasgow's East End cheered to the echo as Celtic easily routed Jim Goodwin's side 6-0 with David Turnbull bagging a hat-trick

The Saints also finished the game with 10-men after a reckless lunge by Alan Power on David Turnbull after just 19 minutes.

A double by Israeli winger Liel Abada and a brace by midfielder Turnbull had Celtic 4-0 up and in total cruise control inside 44 minutes as Ange's men turned on the scintillating style once again and blew the Paisley outfit away.

An Odsonne Edouard goal in the second period saw Celtic go nap before Turnbull bagged his treble as Ange's side claimed their 24th goal in their last six outings.

It was a sixth victory on the spin in all competitions and whilst they may not be the finished article by any stretch of the imagination, Ange's team is starting to take shape rather nicely.

It may well have been a slow burner but the Champions League qualifying defeats to FC Midtjylland and opening day of the season loss to Hearts at Tynecastle are fast becoming a fading memory for the Celtic faithful.

The concept of Angeball appeared to be an abstract one to the Celtic players at first. Slowly but surely the Celtic squad are starting to get to grips with it all.

Under Ange, Celtic artisans resemble a team of Impressionists, Expressionists and Surrealists with a bit of Japanese style thrown in for good measure.

However, the portrait of this artist as a young manager is definitely one of Realism.

Whilst nothing has been achieved yet, Ange is painting by numbers. The next magical number is eight.

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The 55-year-old knows that if he can succeed in guiding Celtic to eight victories in a row by next Sunday then he will have not only seen off the challenge of Dutch masters AZ Alkmaar to qualify for the Europa League group stages but he will also have given Scottish champions Rangers the brush-off and left them temporarily sprawled on the canvas.

Mini-milestones and all that.

That's why the next seven days are so crucial as they will offer Ange and his Celtic team their sternest tests and the greatest gauge of their European and domestic credentials so far.

A trip to Holland to face AZ Alkmaar with a prize in the Europa League group stages at stake followed by a league visit to Ibrox to face Rangers with no away supporters in the ground.

It doesn't get much tougher than that.

If Celtic can emerge from both of those encounters unscathed and post victories in the process then it would be two massive results for Ange's growing portfolio.

It will also give the management team, players and supporters the clearest indication yet that the club is already ahead of schedule even at this early stage of the campaign.

If not and both matches don't go Celtic's way then Ange will simply have to go back to the drawing board.

Although there is a saying that you are allowed to be a work in progress and a masterpiece simultaneously.