After joining Celtic for a figure in the region of £500k back in the summer of 2015, expectations for Ryan Christie's future at Parkhead were extremely high.

It is easy to see why, as, after breaking into the Inverness Caledonian Thistle first team in the club's 2013/14 Scottish Premiership campaign, scoring three goals over 15 league outings, the attacking midfielder went on to cement a starting spot in John Hughes' side the following season, bagging four goals and registering three assists over 35 appearances in the top flight of Scottish football.

And, while still being just 20 years of age upon the time of his move to the then Scottish champions, Christie continued his rather remarkable rise away from Glasgow, during three separate loan spells.

The first of these was back at Inverness, where the Scotland international scored three goals and provided six assists over 13 Premiership fixtures, while the second two loans both came at Aberdeen, with the midfielder bagging 15 goals and registering 18 assists over 57 appearances in all competitions during his two years at Pittodrie.

Upon his return to Celtic, not only was Christe a more developed and well-rounded player, but he was also a more valuable one, with the youngster's Tranfsmarket value rocketing from £225k at the time of his initial move to Celtic to £630k after his three temporary spells away from the club.

This is a trend that would continue at Parkhead, with the £12k-per-week man scoring 11 goals and registering nine assists over 38 appearances in all competitions for the Bhoys in 2018/19. His value then jumped to £3.38m in the summer of 2019 - bagging a whopping 20 goals and providing 16 assists over 45 fixtures in 2019/20. He once again witnessed his value rise in 2020 to £5.85m - and after scoring seven goals and registering 15 assists over 46 appearances in all competitions in 2020/21 his estimations increased to £6.3m at the end of last season.

However, despite these extraordinary returns and his ever-rising value, Celtic somehow allowed the player who Alex McLeish dubbed a "magnificent" talent to enter the final year of his contract at Parkhead without having agreed an extension - something which ultimately led to the Bhoys cashing in on the midfielder for a mere £2.5m this summer.

As such, considering the sheer amount of potential Christie demonstrated during his time in Glasgow, in addition to the fact that the Hoops sold the 26-year-old for a figure £3.8m less than his current Transfermarkt value of £6.3m, it is not a difficult argument to make that the Bhoys had something of a nightmare in the sale of the midfielder.

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