THERE is a reason why club managers watch international football through the cracks between their fingers.

The sight of Kyogo Furuhashi limping out of Japan’s World Cup qualifier against China would have been an immediate jolt for Ange Postecoglou. The Greek-Australian has confirmed that the player will now miss up to a month with a knee injury. Between now and the start of October, Celtic have seven games that will be significant in shaping their domestic and European campaigns.

The Japanese playmaker has quickly assumed hero status after pitching up in Glasgow at the end of July. Having walked into the Celtic side without any cultural crossover transition period necessary, he wasted no time in endearing himself to his new charges.

Furuhashi’s seven goals in nine appearances underline just how influential he has been since settling into Postecoglou’s side, but he has done more than just chip in with goals. His impact has been seismic when consideration is given to the manner in which he helped to lift Celtic after an early Champions League defeat to Midtjylland and opening league defeat to Hearts at Tynecastle.

Furthermore, with the trio of Odsonne Edouard, Leigh Griffiths and Ryan Christie now gone, it means there is an immediate question mark now over where the responsibility for goals lies.

READ MORE: Celtic line-up predictions for Ross County's Premiership visit as Kyogo Furuhashi ruled out injured

Liel Abada’s arrival has been overshadowed somewhat by the form of Kyogo but the 19-year-old has had a fairly impressive start to his Celtic career with four goals and two assists in nine games.

The likelihood, though, is that Greek forward Giorgos Giakoumakis will be propelled straight into the squad to make his debut against Ross County. Forgotten man Albian Ajeti is another consideration but the lack of game-time he has had since Postecoglou’s arrival would suggest that he will not be the first choice to assume that role in Kyogo’s absence.

What the injury to Furuhashi does, though, is expose the limitations within Celtic’s squad and the lack of depth to cope with a two-pronged fight on the domestic and European fronts, a task compounded by the volume of players who will also juggle international commitments.

James Forrest can offer goals and there have been midfield contributions, too, from David Turnbull, Tom Rogic and Callum McGregor but the loss of an out-and-out goalscorer will always be difficult to replace.

Having lost ground at Tynecastle and then Ibrox, Celtic can ill afford to stutter as they seek to build the momentum that will sustain a title push. It is imperative that they find a way to fill the void left by Kyogo’s injury.