After Matthijs de Ligt officially completed his big money move to Juventus
, the market of teenage wonderkids switching clubs for huge fees welcomed a new addition.
Some of the finest stars in world football were acquired as teenagers, while a recent trend has seen clubs pay more and more simply for raw potential.
Sportsmail casts an eye back through the archives to determine the ten most expensive teenagers in the history of the beautiful game.
10 – Renato Sanches: Benfica to Bayern Munich in 2016, £27.5m
and Manchester United were being heavily linked with Sanches when Bayern Munich
swooped in the summer of 2016.
They got the Portuguese starlet for £27.5m but his career has not gone the way they hoped. On loan at Swansea in 2017-18, he fell out of favour, scoring zero goals in 15 games.
His future is still unclear. The plus side is he is only 21 years old, so there is time for the youngster to turn his fortunes around.
9 – Wayne Rooney: Everton to Manchester United in 2004, £27m
Sir Alex Ferguson's club beat Newcastle to the capture of Rooney, who became the most expensive teenage signing in the world at £27m.
What a buy that turned out to be. In 559 games, he scored 253 goals, a club record which previously belonged to the great Sir Bobby Charlton.
Rooney won five Premier League titles, one Champions League and a host of other trophies before leaving to return to boyhood club Everton.
8 – Luke Shaw: Southampton to Manchester United in 2014, £31m
'I want to continue to progress my career and joining United is the ideal place for me to do that,' Shaw said upon signing for £27m, rising to £31m.
It has not always gone according to plan but Shaw has shown signs of getting back on track.
At the end of 2018-19, the 24-year-old was voted Manchester United Players' Player of the Year and Sir Matt Busby Player of the Year.
7 – Lucas Moura: Sao Paulo to Paris Saint-Germain in 2012, £35.5m
Paris Saint-Germain confirmed they had agreed a deal worth £35.5m with Sao Paulo for Moura, who was 19 at the time, in August 2012.
It came as a blow to Sir Alex Ferguson's Manchester United, who had been chasing him.
PSG allowed Moura to stay with the Brazilian side until January before joining them. That seems like ancient history now, with him 26 and at Tottenham these days.
6 – Vinicius Junior: Flamengo to Real Madrid in 2018, £38.7m
Vinicius is of a similar ilk to Rodrygo. Real Madrid paid good money to bring him in from Flamengo because they see him as the future.
'I'm honoured to have reached the pinnacle in football, Real Madrid, at only 18 years of age,' the Brazilian teenager said upon signing.
The forward showed signs of promise in 2018-19. Now 19, he will hope to kick on in 2019-20.
5 – Rodrygo Goes: Santos to Real Madrid in 2019, £40m
Real Madrid have spent £40m on bringing 18-year-old Brazilian winger Rodrygo to the Bernabeu and he is considered a long-term investment.
The forward, who scored nine goals in 41 games for Santos and is said to be blessed with raw talent, may not be a first-team regular yet.
Rodrygo is another boy wonder from Brazil who was sponsored by Nike at the age of 11. They figured he would be worth the money, and so do Real.
4 – Anthony Martial: Monaco to Manchester United in 2015, £58m
Martial became the world's most expensive teenager when he moved to Manchester United back in 2015. The initial fee was £36m, rising to £58m.
Since signing, the 19-year-old has scored 34 goals in 113 Premier League games.
Arsenal wanted Martial at the time too and West Ham were even linked this season. This could be a big season ahead for the now 23-year-old.
3 – Matthijs de Ligt: Ajax to Juventus in 2019, £67.8m
Many consider Virgil van Dijk to be the best central defender in the world. Plenty others suspect this teenager might take on the mantle someday.
In February 2019, he became the youngest-ever captain in a Champions League knockout game, facing Real Madrid at the age of 19 years and 186 days.
The Holland centre back made more than 100 appearances for Ajax, who will miss him.
2 – Joao Felix: Benfica to Atletico Madrid in 2019, £113m
Atletico Madrid signed the Portuguese teenager earlier this month for £113m, making him the fifth most expensive transfer in history and second in this list.
The Spaniards met the 19-year-old's release clause with Benfica, where he made 26 appearances in Portugal's Primeira Liga and scored 15 times.
That won Benfica the title. Atletico, who have tied him down to a lengthy seven-year deal, are clearly confident he will continue to progress with them.
1 – Kylian Mbappe: Monaco to Paris Saint-Germain in 2017, £165.7m
The most expensive teenage signing in history and the second most expensive overall, behind only Neymar to the big-spending Ligue 1 club for £200m.
Mbappe initially joined on loan from Monaco with an option to make the deal permanent. They then triggered that, and have not regretted the move once.
In 2018-19, PSG won their second successive title and Mbappe scored 33 goals in 29 Ligue 1 games. European glory is their next target.