AT THE start of the season, there was only one and the general feeling was two more were needed at Celtic.

Anthony Ralston's encouraging start under Ange Postecoglou negated the requirement for a duo and just one, albeit a starter, was considered needed to improve and bolster the right-back ranks.

He arrived in the form of Croatian international Josip Juranovic but injuries to Greg Taylor initially, with Juranovic also capable of filling in on the left, and then the Croat himself at the end of last month mean Ralston, who has three goals this season, has been continuing in the role.

Whether he is seen as a long-term starter, squad player, or sellable asset is up for debate but the former is unlikely. Depending on Juranovic's success, too, there's the possibility of him being sold in a couple of summers' time when he'd only be 27 years old.

Compared to Ralston, the arc of his career is probably going to reach higher standards given he's a full Croatia international and Parkhead is a stepping stone that's been leapt onto many times before taking the big stride over to one of European football's promised lands. Celtic are a selling club these days, of that there can be little debate. In fact, at varying degrees of the food chain, every club in Scotland is.

That's why at some point in the next year or two, 18-year-old Calvin Ramsay is going to leave Aberdeen - and Celtic should be one of the bigger fish with their eyes on the seal pup up north.

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After taking his baby steps into first-team football at the tail end of last season, Ramsay has had to grown up quickly and has played every game for Aberdeen so far this season.

His ability, directness and confidence is undeniable and he's, quite frankly, shone for a team that are massively underperforming. That's probably why some of the UK's biggest clubs in Manchester United and Everton have, reportedly, already made contact with the Dons to assess his immediate future and how much money it will take to convince Aberdeen now is the time to take the cash.

If he can avoid serious injury, it's a sure thing Ramsay will go on to have a superb career. If he goes down south in January or next summer, the probable outcome is he'll be stuck playing under-23 football for a while intertwined with a couple of loan spells in one of the lower divisions. Staying at Aberdeen or joining an English Championship side, where he'd have a better chance of playing, would surely stand him in better stead for the rest of his career. 

Immediately above Aberdeen in the chain though, are Celtic and Rangers, who usually find themselves having first dibs on any younger player in Scotland that takes their fancy.

Rangers certainly don't need him. They've got the equally, if not more, talented Nathan Patterson whom Everton have also reportedly targeted as a long-term replacement for Seamus Coleman. He's probably the best young full-back in Scotland at the moment and will provide Rangers with a nice profit soon but Ramsay, and Hibs' Josh Doig, aren't far behind in terms of potential.

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Ramsay is a modern-day full-back. WyScout tells us he makes nearly three progressive runs per game, more than Jeremie Frimpong averaged in season 2019-20, and in one instance against Ross County at the end of August, he managed eight of them.

He's regularly fouled, which leads to chance creation, and wins half of his offensive duels - not bad for a teenager who's yet to really make the transition from boy to man.

His set-piece deliveries are a treasure for Aberdeen as well and he's racked up five assists already this term, including the cross that led to Lewis Ferguson's equaliser at the weekend. Nearly two-thirds of his dribbles are successful too, the same ratio as his forward passes, so his attacking stats are impressive given he's in his first full season as part of a first-team squad.

He's a right-back, though, so enough about this attacking stuff. Can he defend?

Well, he's getting there. Ramsay wins more than half of his defensive duels on the ground and in the air. He's only slid in to win the ball seven times since the season started but his interception rate is decent as well, making around half a dozen of those per game.

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Domestically, though, while it's important for any of Celtic's penultimate line of defence to be able to thwart the opposition and react to counter attacks, more often than not their full-backs are tasked with helping to break down stubborn low-blocks and find inventive or quick ways through them. It's vital for a full-back to thrive with such demands, and why Kieran Tierney and Frimpong, on occasion, were so important for Celtic.

Is there a need for Celtic to sign Ramsay or would the club just be stunting the career growth of another young Scot? It might depend on how long Josip Juranovic is expected to be at the club or if Postecoglou is keen to play him at left-back in the interest of securing and developing one of Scottish football's brightest prospects.

With the packed schedule the club's players face, Ramsay and Celtic could both benefit from a transfer. It'd probably benefit Ramsay more than a transfer to the PL2.

Whether Celtic are willing to pay whatever Aberdeen demand - remember this is a club that let John McGinn slip through their fingers - is another matter.

But if they do then Celtic would be pretty certain to make a nice return on that investment whenever Ramsay was sold on - and a damn fine player for the here and now into the bargain.