Celtic enjoyed a rampant summer transfer window with no fewer than 12 first-team players being welcomed through the Parkhead doors by Ange Postecoglou.

However, January arrivals are looking a little more troublesome for the Australian boss with huge transfer fees potentially having to be spent.

What's the word?

It's no secret that the Hoops will need £6.5m in order to lure Jota to the club on a permanent basis and for a man of his talents, it seems a plausible deal to complete.

However, if they want to land fellow loanee, Cameron Carter-Vickers, permanently they will have to cough up an even steeper fee.

In a fresh report courtesy of the Daily Record, it hands a hammer blow to Celtic's chances of acquiring his signature next year.

Carter-Vickers signed a new one-year extension with parent club, Tottenham, before agreeing on a temporary switch to Parkhead. Yet, it's now been claimed that the Bhoys will need as much as £10m in order to activate a full transfer.

Significant blow

This is news that is likely to leave Postecoglou fuming, such is Carter-Vickers' importance to the Celtic side this season.

The American has made an instant impact in Glasgow, hammering home an effort from range on his debut against Ross County back in September.

Since then, he's gone from strength to strength while in the famous green and white hoops, winning a colossal 4.1 aerial duels per game, the third-highest in the manager's ranks.

Furthermore, his tally of 1.2 interceptions per appearance is the fourth largest number when compared to the rest of his colleagues.

What's elevated his status so quickly in the Celtic side is a number of defensive injuries. Christopher Jullien hasn't been seen all year while Carl Starfelt and Stephen Welsh have recently suffered from their own fitness problems.

Celtic have hardly been perfect from a defensive point of view this term either, keeping 11 shutouts in 28 matches this term but that's primarily been down to a lack of depth.

Thus, signing Carter-Vickers permanently, either in January or next summer, would have been an important addition to their ranks.

Instead, they are left staring at a potential £10m transfer fee, one they are unlikely to pay when you consider that Odsonne Edouard remains their record signing at £9m.

They do, of course, still have plenty left in the bank following the sales of Kristoffer Ajer and Edouard a few months ago, but this will come as nothing other than a blow to their chances of landing the central defender.

Considering how well the 23-year-old has taken to life under Postecoglou, this revelation is sure to leave the manager rather angry and dismayed.

AND in other news, Huge boost: Alan Nixon delivers promising Celtic update that will leave fans buzzing...