CELTIC resume domestic action buoyed by an eight-match unbeaten run including seven victories.

The only concern for Ange Postecoglou is the international break interrupts that momentum but, given the likes of Callum McGregor and Josip Juranovic enjoyed excellent games for their nations, it could also act as a booster for a few of the Celts.

A curious byproduct of these windows is that, for some, it actually provides a chance for much-needed rest.

The most obvious examples are injury-enforced – such as Tom Rogic and Carl Starfelt – but others can get some time off even while called up.

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David Turnbull, for instance, made a one-minute cameo appearance against Moldova but apart from that was a virtual spectator on Scotland duty.

Given he is currently leading Celtic in minutes played so far this season, the disappointment of fleeting involvement in dark blue might prove a benefit in keeping his legs fresh for his next run of fixtures in green and white.

First up for Turnbull and co. is the League Cup semi-final against last season’s double winners St Johnstone.

Here, we take a closer look at Callum Davidson’s Saints...

How have St Johnstone fared this season?

They started the campaign with just one win in 10 games – on penalties against second-tier Arbroath in the League Cup – but they did hold Galatasaray and LASK to confidence-boosting home draws in their European qualifiers during that run.

Since their continental adventure ended on August 26 their form has been pretty even with four wins, four defeats and three draws.

Celtic Way:

Saints now sit ninth in the Premiership and are unbeaten in three matches (albeit that includes two draws). They signed off for the international break with a profligate 0-0 draw against St Mirren that Davidson described as “really poor”.

How are they expected to line up?

The guts of the team that created history last season is still there, even if some of its spine has been removed.

Summer exits for captain Jason Kerr and influential midfielder Ali McCann, to Wigan and Preston respectively, have undoubtedly made Saints a weaker side overall but they still carry plenty of threat in multiple areas.

Saints tend to utilise a back three/five in front of goalkeeper Zander Clark. They kept to roughly that shape in October’s visit to Parkhead and, although the Perth men could take very little confidence from that display, there is no reason to think Davidson will deviate much from that on Saturday.

As such, the likelihood is former Hoops youth Jamie McCart and newly-appointed captain Liam Gordon will combine with either ex-Celt Efe Ambrose or Millwall loanee Hayden Muller. The latter has started the past couple of matches while Lars Dendoncker and Shaun Rooney have played in the defensive trio this term too.

Callum Booth is pretty secure in his left flank berth while Rooney is likely to start on the right. Michael O’Halloran and James Brown have also featured there, with the latter an outlier shout to start in the back three if Davidson wants to combat Kyogo's speed with some of his own.

Celtic Way: St Johnstone predicted line-upSt Johnstone predicted line-up

In midfield there are plenty of names to consider, including club stalwarts Murray Davidson and David Wotherspoon, while Ali Crawford and Craig Bryson have all clocked up game-time and veteran Liam Craig has played every minute of the League Cup campaign so far.

Up front will be Chris Kane – easily confused with his wrestling namesake after his exploits at Parkhead – with the injuries to Stevie May and Glenn Middleton perhaps precipitating a shift forward for O’Halloran or a surprise start for Finnish forward Eetu Vertainen.

It is worth noting that Celtic have had mixed results against variations of the 3-5-2/5-3-2 this season, losing to both FC Midtjylland and then Hearts in the Premiership opener as both created chances by exploiting space behind the full-backs with quick, direct wing play.

On a more positive note, though, on the last two occasions the Hoops have had to contend with a team playing that type of system – against Hearts in the League Cup and the Saints themselves at Parkhead – Postecoglou had a few more players available and generally made short work of both as a result.

Who are their main danger men and how will they try to hurt Celtic?

It seems odd to single out a keeper as a ‘danger man’ but Clark’s performance will likely be vital if Saints are to keep Celtic at bay and make another happy Hampden memory.

The 29-year-old has earned a place in the Scotland squad in recent months and has arguably been the standout custodian in the division so far this season in terms of performance versus expectation.

Celtic Way:

Clark has conceded the second-fewest goals (level with Dundee United’s Benjamin Siegrist behind Joe Hart) and is top of the charts by some distance in goals saved above average. Essentially, his saves have prevented Saints from conceding almost seven goals more than they have.

StatsBomb notes that Saints have given up 26 mid-to-high-quality chances (25 excl. penalties) inside their own area this league season. Around 20 of those chances came in particularly close, central areas with five resulting in goals and Clark saving 11.

Celtic, by the same metrics, have allowed 12 big chances inside their box but have conceded six times from them.

As an intriguing aside, the Hoops have conceded just three quality chances in the league from set-plays (corners, free-kicks and throw-ins) with only John Souttar’s winner for Hearts in August resulting in a goal.

Celtic Way: Zander Clark has saved 11 big chances in close, central areas this league seasonZander Clark has saved 11 big chances in close, central areas this league season

However, broaden that out to any chance conceded from a set-piece and the reason for the team’s perceived fragility in those situations shines through in the shape of costly individual errors: a further three concessions - v Rangers, Hibs and Aberdeen - with each eminently preventable and a potential avenue for Saints to try to exploit.

Indeed, a league-leading defensive record though it may be, the Hoops have also conceded half of their eight goals from open-play crosses into the bargain.

Yet at the back St Johnstone are something of a contradiction themselves.

WyScout ranks them third for defensive duels per 90 as well as interceptions made per 90 suggests a dogged, disciplined team but clocking in as third-worst for challenge intensity and worst for ball losses would point to a team not actually very efficient in those actions.

But can they play?

On a day that will see plenty of tributes paid to Cetlic legend Bertie Auld, that is perhaps the most pertinent question.

Saints have generally struggled to find the net; Kane is the team’s top scorer with three goals in 18 matches while May, Crawford and O’Halloran are the only other players to net more than once.

Defender Rooney – whose great-uncle Benny was a former Celtic youth and great-grandad Bob a former Hoops physio – had the distinguished honour of scoring the winner in both cup finals last term and will no doubt fancy his chances again at his happy hunting ground.

His historic final goals, as well as another at Hampden in the semi against Hibs, came as a result of headers from crosses (one a corner, one a free-kick and one from open play) but is that reflective of Saints in general?

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The Perth men rank second bottom of the division for key passes and through balls and are a middle-of-the-road side for virtually every other aspect of play construction (for instance, deep completions, progressive runs, long passes, etc.)

But the perception that Saints are a particularly dangerous threat in the air - naturally perpetuated by those Rooney goals last season - is somewhat wide of the mark statistically.

They're also second for aerial duels contested but drop to third worst for actually winning them (Celtic are, perhaps surprisingly, top of the table in this regard) while they have taken the fewest headed shots and put in only around the league average amount of crosses.

However, Saints proved by making the national stadium their own personal trophy room earlier this year that they are anything but average in the landscape of Scottish football... and it is up to Celtic to make Hampden theirs once again.