CELTIC edged closer to their fifth treble in seven years at Parkhead this evening when they beat their cinch Premiership rivals St Mirren to progress to the quarter-finals of the Scottish Cup. 

Yet, the emphatic 5-1 win came at a cost for the Scottish champions as Kyogo Furuhashi had to go off injured early on following a heavy fall.

If the Japanese internationalist is ruled out of action for a prolonged period of time it could have a detrimental impact on the Glasgow club’s bid to complete a clean sweep of domestic silverware.

The £4.6m signing is the leading scorer in both the league and the country in the 2022/23 campaign with 19 and 22 goals respectively.

His understudy Giorgos Giakoumakis departed for Atlanta United in the United States earlier this week and new signing Oh Hyeon-gyu is, despite coming on and opening his account, still finding his feet. 

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Celtic are nine points clear at the top of the Premiership, in the Viaplay Cup final and through to the last eight of the Scottish Cup. They showed once again today they are the best in the country by a distance. But not having Furuhashi will be far from ideal.

That said, the loss of their on-form front man did not affect the home side’s display today. They ground out a hard-fought but ultimately comfortable triumph in a thoroughly professional manner.

Daizen Maeda opened the scoring in the first-half, Reo Hatate netted from the penalty spot in the second after Richard Taylor had been red carded following a interminably long VAR check, Oh bagged an opportunistic effort, Matt O’Riley got in on the act in the final minute and Hatate added another in injury-time.

Mark O’Hara slotted a consolation goal for St Mirren from the spot with four minutes of regulation time remaining after Carl Starfelt had fouled Greg Kiltie. Here are five things we learned from the last 16 encounter.

TREBLE YELL

Having never lost a domestic fixture at home under Postecoglou, the scoreline when referee Steven McLean blew his final whistle was no great surprise.

Yet, the visitors were the last Scottish team to beat them both in a domestic competition and on their own turf. So it was not entirely inconceivable that Stephen Robinson’s men, in sixth spot in the Premiership table and in with a chance of European qualification, could spring another fifth round shock. 

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Postecoglou certainly took the threat the visitors posed seriously and fielded a full-strength team. He was wise to as it proved to be a fiercely contested 90 minutes. Celtic were made to work on their place in the quarters.

If they do lift every piece of silverware this season – and on this evidence there is a very good chance they can - they will look back on this assured victory as being pivotal to their success.

MAEDA MAGIC

Maeda may have played as striker for Japan in the World Cup back in November and might have scored against Croatia.

But it is fair to say the industrious and direct forward is at his best out wide and lacks the finishing ability of Furuhashi.

The 25-year-old, though, is certainly no slouch between the posts as he showed when he broke the deadlock following good build-up play by Alastair Johnston, Liel Abada and Aaron Mooy.

He also hit the woodwork twice before returning to the wing when Oh came on. He was one of the stand-out performers on the pitch. He will continue to play through the middle if his compatriot is sidelined in the weeks ahead and cause all kinds of problems for opposition defenders. 

OH OH!

Postecoglou has stressed that it will take Oh, the South Korean internationalist who joined in a £2.5m transfer from Suwon Samsung Bluewings in his homeland last month, a little time to get up to speed.

But the 21-year-old has grown in confidence and influence with every appearance he has made and took his goal well this evening. He pounced on a loose ball in the St Mirren area and fired beyond Trevor Carson. It will boost his self-belief no end.

TURNBULL CHANCE

Postecoglou made just one change to the side that had beaten St Johnstone 4-1 in Perth in the league six days earlier; David Turnbull took over from Hatate in the centre of the park.

Turnbull has, with Hatate, Callum McGregor, Mooy and O’Riley all enjoying such good form, found first team starts hard to come by this term.

This was just the second time he had kicked off a game since club football resumed after the Qatar 2022 finals in December – and the only other occasion he did so was against second tier Morton in the fourth round of the Scottish Cup last month.

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The 23-year-old had netted three times in five appearances before today and his manager clearly felt he was deserving of an extended run-out.

Turnbull, whose representatives are in talks with Celtic officials about a contract extension, did well enough before being replaced by Oh in the second-half.

The Scotland internationalist, however, must do far more if he is to be involved more during the run-in. He was unable to make a significant impact on proceedings.  

YOU WATT!

St Mirren showed exactly why they have enjoyed such a good season in the East End of Glasgow; they were well-organised, physical, hard-working and broke upfield in numbers on several occasions without really testing Joe Hart. 

Alex Grieve limping off injured after a collision with Hart shortly before half-time was a blow to the SMiSA Stadium outfit. Tony Watt, the former Celtic striker who has joined from St Mirren on loan until the end of the season, came on and ensured there was no drop in performance level from the away side.

If Robinson can continue to get a decent shift out of the mercurial talent in the remainder of the season he will have a potent weapon at his disposal.