Sunderland's traversal of the Premier League, Championship and League One in recent times has seen their transfer strategy change immeasurably.

This has seen them go from spending £18m on Didier Ndong whilst in the Premier League to landing Aiden McGeady for just over £250k in the Championship and the current iteration of signings in League One under Lee Johnson, such as Callum Doyle and Leon Dajaku, on loan.

Along with their signings, the Black Cats have also made plenty of sales along the way. An unfortunate side-effect (beyond the obvious) of being relegated is that a club's promising young talents may get snapped up by those further up the footballing ladder.

This was the case in 2018 when Joel Asoro was sold to Swansea following the Wearsiders' relegation to League One. The Swedish attacker recouped the club a reported £2.07m through his move to Wales at the age of 19, but was it the right call?

From Sunderland's perspective, they will be over the moon with the deal in hindsight due to what he has gone on to do since leaving the Stadium of Light. As per Transfermarkt's valuation system, he is currently valued at a paltry £405k and is playing in Sweden for Djurgarden.

This means that his value has dropped £1.66m from £2.07m upon his sale in 2018 to £405k currently. His valuation would need to increase by over 500% for him to reach the level he was at when he joined Swansea, which highlights how far he has plummeted as a player since departing Sunderland.

At the time of the sale, Asoro had built a decent reputation after scoring three goals and setting up two in 26 Championship appearances for the Black Cats. This was a solid return for a teenager making his first foray into professional football, suggesting that he had the potential to go on to greater things.

However, it clearly has not worked out that way for him. He failed to score in 18 senior appearances for Swansea and now finds himself plying his trade in Sweden at the age of 22. This shows that Sunderland struck gold by selling him when they did.

Given his form since leaving the club, Asoro may have gone on to flop with the Black Cats, and then they would never have been able to sell him for as much as they did. Hindsight is a wonderful thing, of course, but Sunderland will surely be looking at his current situation and feel thankful that they decided to cash in on him when Swansea came knocking for £2.07m.

They managed to strike gold at the perfect time and, unfortunately for Asoro, it has been all downhill for the player since then. It is a shame that he has not been able to live up to his early potential, but purely from his former club's perspective, they will be delighted that they made the most of his value in 2018 given what has happened since.

AND in other news, Phil Smith drops claim on £1.6m-rated “top prospect” which will excite Sunderland fans...