When the opportunity arose, Tottenham Hotspur simply couldn't resist bringing Sergio Reguilon to the club for just £25m and what a signing he has been.

Before his recent injury, the 24-year-old was one of Jose Mourinho's most consistent performers (6.87 average rating) and a vital source of goals, only Harry Kane and Heung-min Son have managed more assists (three) in the Premier League this term.

Although, there was always one downside to the deal as Real Madrid inserted a buy-back clause that runs until summer 2022, in which they can re-sign the Spaniard in a move that would see Spurs make £15m profit.

The player would have to agree to the return, of course, but emerging reports suggest that the La Liga giants could indeed come calling sooner rather than later.

According to Eduardo Inda at El Chiringuito, Reguilon has already said 'yes' to a potential reunion at the Bernabeu ahead of the next transfer window, which would come as a huge blow to Spurs considering his form so far this term.

If this report does come to fruition, then Mourinho must find an alternative option and perhaps he already has an ideal replacement waiting in the wings in the form of academy sensation Dennis Cirkin.

The 18-year-old was named as Spurs' young player to watch out for in 2021 by The Athletic at the start of the year, even despite the U23 starlet never making a senior appearance for the club.

It's claimed by the reliable Charlie Eccleshare that but for persistent injury problems, Cirkin would have made his first-team bow this season following in the footsteps of Alfie Devine and Dane Scarlett among others.

He goes onto suggest that it is only a matter of time before he plays under Mourinho as the 'Special One' singled out the teenager for praise just two weeks into taking the Spurs job, he said:

"OK, he’s 17, but he’s a kid with a lot of quality, and I look forward to bringing him to train with us and to help his development."

Indeed, Cirkin has been a frequent presence amongst the first-team training and Reguilon's form certainly makes his job harder but if the Spaniard were to leave, then the door would finally open.

The Athletic also believe that the young Irish gem is energetic, strong in the tackle and very positionally aware, which is very much of similar ilk to Reguilon as shown by his attacking influence mentioned above.

Cirkin could help Daniel Levy and Spurs save a lot of money this summer, but that all depends on whether or not the five-time Spanish international returns to the club that didn't trust him in the first place.

AND in other news, £20.25m-rated titan who "shows no nerves" would be perfect for Spurs