Ange Postecoglou's pre-World Cup cautionary note to Celtic fans forewarned the prospect of waving goodbye to some Parkhead favourites.

But as the January transfer window looms, the Premiership champions could end up with more Qatar ins than outs. Canada right-back Alistair Johnston arrived in Glasgow on Monday after signing a five-year deal to join from CF Montreal, and he could yet be joined by another who caught the eye on the biggest stage of them all. South Korea striker Gue-Sung Cho has emerged as a potential target, and he's seemingly set to make a decision on his future before too long.

The only certainty at this point is the Jeonbuk Hyundai Motors forward has his heart set on cracking Europe, and there's no shortage of interest. Fenerbahce and Ferencvaros have been named as keen suitors, two clubs Celtic will likely feel they can outwit in the market. Cho has asserted his primary consideration for a transfer is simply who can offer him the most playing time, telling South Korean TV: "Rather than dreaming of signing for one specific club, for me, being able to play every week is the most important aspect of any move and that's what will influence me. But I can honestly say there is nothing concrete about a transfer yet. I am still a player of Jeonbuk Hyundai. I also want to go.”

Given Celtic's wealth of options in attack, a permanent starting berth is unlikely, but the player will know that such things are earned and not simply promised when you sign a contract. That Celtic's interest in Cho surfaced alongside news that Giorgos Giakoumakis could potentially leave is probably no coincidence, and another sign that the club are working hard to stay one step ahead in the transfer market, a real comfort for supporters if and when existing first-team stars move on. Should Giakoumakis depart, he's reportedly unhappy with contract terms being offered, only to be swiftly replaced by Cho, it would be another potentially seamless transition in the same vein as Alistair Johnston arriving amid speculation Josip Juranovic is for the off.

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Cho and Giakoumakis are certainly comparable. Celtic's Greek international has an impressive strike rate, scoring eight times in 22 appearances, a number of which have been from the bench. Cho, meanwhile, has 11 in 20 in the K-League. Stylistically, he would allow Postecoglou to retain the level of variety in his forward line he currently enjoys with Kyogo and Giakoumakis. Standing at 6ft 2, Cho would be a very different foil to Kyogo, and his brace against Ghana in Qatar offered a snapshot glimpse of what he's all about. His second strike, in particular, was reminiscent of what Celtic fans have come to expect from Giakoumakis; powering above defenders at the back post and finishing first time in the six-yard box.

As well as providing a significant goal threat, the 24-year-old is a real grafter. Unusually, and perhaps, refreshingly, for a striker, he even singled out his defensive contribution as being among his strongest attributes. “My strengths include heading, but I think defending is also my strength," Cho said. "I try to reduce the burden on defenders, midfielders, and goalkeepers by fighting from the front and participating in defending. Even when it is difficult, that seems to be my strength.” Being a willing worker is a prerequisite in a Postecoglou team, and it's clear this is a demand Cho would relish.

He certainly fits the bill, but a January arrival likely hinges on where Giakoumakis ends up come the window's end. The prospect of having three top strikers on the books is an enticing one for supporters, but perhaps less workable in practice. It certainly makes for an interesting few weeks ahead, especially if the possibility of Giakoumakis moving on becomes a reality. Postecoglou has proven a dab hand in navigating the J-League market, and previously revealed he's also been following the K-League closely. You do wonder if his success rate in bringing players to Europe from far afield could have in influence on Cho's decision. Upon being unveiled on Monday, Johnston revealed he was encouraged to choose Parkhead by Postecoglou's track record, which, of course, includes the likes of Kyogo Furuhashi, Reo Hatate and Daizen Maeda. It certainly makes sense that Celtic would put this forward as a unique selling point when competing with other clubs for players, and it may just give them the edge over others if the race for his signature goes right down to the wire.

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Either way, the situation is another example of Celtic being prepared to be "aggressive" in the market, as Postecoglou detailed before the World Cup break. He cautioned that such a strategy would see fan favourites moving on, perhaps before punters expected, but those losses will be significantly softened if Celtic continue to line up replacements well in advance. The club's transfer strategy has been impressively streamlined under Postecoglou, and the efficiency of business conducted last January is now becoming a consistent theme.

Signing Cho could be the latest step on an exciting path.