There has been plenty of chatter of ‘Groundhog Day’ on The Celtic Way in recent weeks and months – on the site and the morning briefing - with many sectors of the club being described as such.

It is a negative expression, its definition being the same event happening over and over again in exactly the same way. Whilst that might not be completely the case with Kieran Tierney’s entire post-Celtic career, it does hold some validity, unfortunately.

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On Friday afternoon, Scotland coach John Carver uttered the unfortunate news that no Scotland, Arsenal or, indeed, Celtic supporter wanted to hear – that Tierney’s injury was another serious one. Carver told the media in Germany: "He is heading home to be assessed by Arsenal and that's all I can really say at the moment. They will give updates as they have it, but he is obviously extremely disappointed.

“If we do progress and move through the tournament, I am sure he will be back to support us. It is a blow because Kieran is one of our top players and, in tournament football, you need your best players on the park And, in particular with him, he gives that balance down the left-hand side with Andy Robertson and Callum McGregor, and they combine really well.

"So whenever any team loses their best players then it will affect the situation, but also it is an opportunity for somebody else to step in."

It sounds a lot like the aforementioned “Groundhog Day” for the former Celtic left-back, doesn’t it? Injuries have unfortunately been the recurring story of the Scotland stalwart’s career following his £25 million move from his boyhood club to Arsenal back in 2019. In truth, spells on the sidelines were occurring before that point, with Tierney regularly playing through the pain barrier to be able to turn out for the team he supports.

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A quick glance at Tierney’s injury record on Transfermarkt.co.uk paints a vivid – but not a pretty - picture of why the left-back has struggled to kick on in his career in recent years. A massive 17 separate injuries are attributed to the defender, including three separate layoffs during his loan spell in Spain at Real Sociedad – a move generated to get him more game-time away from London.

On further inspection, it seems as if the problems started in Tierney’s final season at Celtic during the 2018/19 campaign, particularly with his hip. The player missed over 20 games because of this injury, coupled with calf and groin issues, with the latter requiring surgery to repair. Since this point, Tierney has not gone through a single season without picking up an injury at some point, ranging from his shoulders, hamstrings, knees and ankles. Nowadays – fairly or unfairly – you associate Tierney with injuries, rather than the outstanding left-back, who is a fan favourite when fit and available.

What does this have to do with Celtic, you might ask? For the past few years – because of his failure to hold down a starting spot in North London – Tierney has played a bit-part role for Mikel Arteta and Arsenal, not helped by the arrival of Oleksandr Zinchenko from Manchester City. Because of this, the rumour mill seems to have been swirling concerning a potential return to his beloved Celtic, a move that would have been universally welcomed a couple of years back.

Presently, however, I’m not so sure if that is the case. You see, supporters keep a keen eye on those players that have left for pastures new, and even more so with ‘one of their own’. They are aware of the form that a player is enjoying – or enduring – as well as their injury issues. The Celtic fanbase is a passionate group, but a clued-on one too. The club will have a hectic schedule this season, following last campaign’s rollercoaster ride under the returning Brendan Rodgers. At least eight games in the revamped Champions League are guaranteed, as well as domestic participation in the Scottish Premiership, League Cup and Scottish Cup.

With all of that to contend with, I think that it is time to kiss goodbye to any faint chance of Tierney returning home in a playing capacity for Celtic in the future. There is now an air of inevitability when he takes to the field that an injury is not too far away in the distance, even when he does manage to play a good number of games consecutively. When Celtic’s former number 63 fell to the floor clutching the back of the leg, you immediately feared the worst for the defender, with those worries vindicated just hours later by his international coaches.

No two ways about it: Celtic do need a left-back – or two – this summer. Greg Taylor – one of Tierney’s original replacements - has been an admirable first-team full-back over the past five years, but you get the vibe that Rodgers will be looking for an upgrade in this area. With big-money signing Alexandro Bernabei so far out of the picture on loan in Brazil, this is an area that needs strengthening, and then some.

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On paper, Tierney would be a bona fide upgrade in this position. Strong at the back defensively and a menace going forward, a fully-fit ‘KT’ would be a revelation in Celtic’s current, especially under his former manager. Unfortunately, you cannot look past his injury troubles, most recently at the Euros for Scotland. This is before you even begin to consider the wages that Celtic would have to fork out for the player, either on a temporary or permanent basis.

Everybody loves a reunion story, especially in football concerning transfers. However, this comeback story – for a multitude of reasons – cannot feasibly happen for Tierney. An undoubted shame, but Celtic and Rodgers must put the good of the team over any happy homecoming regarding themselves and the unlucky left-back.

Alas, Celtic's summer search for an upgrade at left-back continues…