IT is a defining moment of the season for Ange Postecoglou and Celtic.

The Aussie can steer his new look Celtic side into the first domestic cup final of the season.

The men from Glasgow's East end ended last season trophyless and also failed to reach the showpiece on both occasions in the League and Scottish Cup competitions.

Ange's men will be the overwhelming favourites to see off holders St Johnstone but Callum Davidson's side showed exactly what they are capable of by lifting the two pieces of domestic silverware last season.

That recent experience of winning at Hampden will surely stand the Saints in good stead ahead of this one.

It is a critical time for Ange as he attempts to rebuild Celtic as he continues to construct, in his own words, a 'beautiful house'.

READ MORE: Celtic v St Johnstone preview and the curious byproduct of David Turnbull's Scotland absence

Here are three key issues ahead of the game.

New regime, same old Celtic

This is a massive match for Ange and Celtic in the context of the club's campaign The Aussie as well as many of his players will be making their first appearance at Hampden.

All parties will want to show that Celtic have the bottle to handle a game of this magnitude against a Saints side who are used to winning at the national stadium after plundering both the League and Scottish Cup last season.

This is the opportunity that the Aussie has craved all along in management and if he wants to be a successful and winning manager in European football then this is a game where defeat is not an option.

There is an air of confidence rightfully sweeping through Celtic and their supporters at the minute and rightly so.

The manager just has to guard against the feeling that this semi-final is a foregone conclusion as it is not by any stretch of the imagination.

However, you get the feeling that whilst Ange and his side will want to lay down an early marker by reaching the League Cup final they will not be satisfied or content with that achievement alone. Celtic will want to go and complete the job and land the silverware.

Only then will Ange and his men fully convince that whilst it may be a new regime in Paradise it is the same old Celtic having returned to their familiar trophy-winning ways.

Injury to Giakoumakis only highlights recruitment need in January


Celtic Way:

The Greek hitman has had a slow start to life at Parkhead and has failed to hit the ground running in a Celtic jersey.

The news that he has been struggling with a knee injury during the break which has ruled him out of such a crucial match will no doubt set alarms bells ringing with Ange and the supporters.

There is a player in Giakoumakis somewhere but the faithful's jury is still out on last season's Eredivisie's 26 goal top scorer after he blotted his copybook by missing a last-gasp spot-kick against Livingston.

READ MORE: Bertie Auld remembered: The Celtic force of nature with a rapier wit and heart of a Lion

With the opening of the January transfer window, it may well strengthen Ange's resolve to bring in another striker to aid Kyogo in the shape of compatriot Daizen Maeda.

The 24-year-old Yokohama F. Marinos striker is the current J-League top marksman and that has led to heavy speculation that he is on his way to Celtic.

Maeda is an inverted left winger who can also play through the middle as the main striker.

Like Japanese bhoy Kyogo - who has become a talismanic figure for Celtic since his arrival in the summer - the temptation for Ange to recruit another fast, lethal option in the final third to provide stiff competition for places may well prove too great and it would be no surprise to see Maeda in Glasgow come January.

Make "Ten-Thirty" proud and do it for Bertie:

Celtic Way:

There will definitely be a poignant and emotional tinge to this semi-final occasion at Hampden as Celtic remember the dearly departed Bertie Auld.

Every player on Ange's side will also sport the No.10 as a mark of respect and tribute for the legendary Lisbon Lion midfielder.

However, this is one such match where the Celtic players will be reminded to play the game and not the occasion and not let their emotions get the better of them.

Bertie's mantra was always to go out there and "entertain".

How fitting a tribute would it be for Bertie if the current crop were to dazzle in the national stadium?

Bertie once famously quipped that under Jock Stein in the 1960s "Hampden was a second home because Celtic appeared there so often."

If Ange's men do as Bertie would have wanted and "entertain" then a place in the League Cup final surely awaits.

The Aussie will also be hoping that Celtic can take the first step by reaching the final and go on to make visits to Hampden a regular occurrence.