Celtic may well have been left to rue their failure to land Scotland international Scott McKenna just over four years ago, with the current Nottingham Forest man having gone on to become a key figure for both club and country.

Reports back in 2018 suggest that the Hoops had seen an offer of around £3.5m rejected for the then-Aberdeen colossus, with those at Pittodrie having reportedly been demanding a fee of around £10m if they were to sanction a sale.

The towering centre-back subsequently submitted a transfer request a year later in order to engineer an exit from the Scottish Premiership side - amid interest from a number of Football League clubs - with the Old Firm outfit having been said to have made a 'substantial offer' in the January 2019 window.

As it proved, the 6 foot 2 brute was ultimately snapped up on a £6m deal by his current side in the summer of 2020, with the defender having since gone on become a vital presence at the City Ground.

There may well be a great sense of frustration that the Glasgow side - then managed by Brendan Rodgers - were unable to strike a deal in 2018, with potential question marks over whether the club could have made a more sizeable offer, particularly considering they would go on to fork out for £7m for Christopher Jullien instead a year later.

Pundit Peter Grant has since noted his astonishment that Rodgers - who admitted his interest in the player at the time - wasn't able to secure his signature, stating:

“I 100 per cent thought that Celtic would take him from Aberdeen because he is a natural left-sider and they were only going to make money from him because he was only going to get better.

“I can’t believe they didn’t go for him. He was available and it’s so key to have a left-sided player in the modern game. He’s like an old school centre back. There are no tattoos. You can imagine him in the pub playing darts. He doesn’t get carried away with all the trappings of it he just wanted to get better.

"His distribution can be better but defending is his thing and he’s very good at it."

That glowing praise comes amid what has been an impressive two years for McKenna in England, as he has gone on to rack up 83 games in all competitions for his current side thus far, scoring three goals and laying on four assists in that time.

That haul includes a tally of two goals and three assists in 51 games last term as Steve Cooper's side secured promotion to the Premier League, while the £6.3m-rated man has gone on to start all seven games in the league in the current campaign.

At international level, the 25-year-old has also impressed of late, notably starring in Scotland's impressive Nations League group stage performance, recording two clean sheets from his four outings, winning 93% of his aerial duels and recording an impressive 91% pass completion rate.

Clearly a player who can offer quality defensively but also in possession - having been lauded for having a "hell of a lot of attributes" by the aforementioned Grant - the £15k-per-week man could well have thrived under current Hoops boss Ange Postecoglou, with the title-winning coach currently lacking a left-sided option at the heart of the backline.

As it is, it looks as if McKenna will be a case of what-might-have-been as far as Celtic are concerned, with the champions set to have to see the 28-cap rock continue to impress both for his club and on the international stage.