Real Madrid smashed their transfer record this week by signing Yan Diomande for £107 million, one of the biggest ever fees for a teenager in the history of football. The 19-year-old could end up costing the Spanish club up to £120 million if potential add-ons are met – but where does he rank among the most expensive players under the age of 20?There are some gems in this list, but a couple of flops, too. The five biggest transfer fees ever paid for teenagers:5. Matthijs de Ligt – Ajax to Juventus, £77mWhen Juventus landed Matthijs de Ligt in 2019, it felt like something of a coup. The Dutch defender was one of the key men in Ajax’s fairytale run to the semi-finals of the UEFA Champions League that year while leading the club to a league and cup double. He did so as captain at just 19 years of age. The youngster never recaptured that form in Italy, though he did win a Scudetto and Coppa Italia while there. The Old Lady recouped most of the £77 million transfer fee they paid for him by selling him to Bayern Munich in 2022, but he was similarly ineffective in Germany. Just two years later De Ligt he was sold for another big fee to Manchester United, where he has somewhat reinvigorated his career, although injuries have limited his playing time. 4. Jude Bellingham – Borussia Dortmund to Real Madrid, £88.5mJude Bellingham has been a prodigy since he first arrived on the scene as a 16-year-old at Birmingham. He was always destined for greater things, joining Borussia Dortmund for £25 million in 2020. After three impressive seasons in the Bundesliga, Bellingham was sold to Real Madrid for £88.5 million, which could rise to £115 million with add-ons, just a couple of weeks shy of his 20th birthday. It has turned out to be an excellent purchase by Los Blancos. The England international made an immediate impact, scoring 14 goals in his first 15 games, surpassing Cristiano Ronaldo, Alfredo di Stefano and Pruden’s previously jointly-held record of 13. Real won the La Liga and UEFA Champions League double in his debut campaign for the club, though they haven’t lifted either trophy since then. But few would bet against Bellingham leading the Spanish giants to further glory in the near future. 3. Yan Diomande – RB Leipzig to Real Madrid, £107mTime will tell if Yan Diomande will turn out to be money well spent, but there can be little doubt that the winger is one of the most exciting young prospects in football today. The 19-year-old registered 13 goals and 10 assists in 36 appearances for RB Leipzig last term before impressing at this summer’s FIFA World Cup with Ivory Coast. There’s a reason why Arsenal, Liverpool, Manchester City and Paris Saint-Germain were all in for him. Diomande will certainly be one to watch this season. Read – The most expensive African footballers of all time2. João Félix – Benfica to Atletico Madrid, £113m When Atletico Madrid broke the £100 million barrier to sign a 19-year-old João Félix from Benfica in 2019, it appeared as if they had landed the next big thing. The Portuguese attacker was a truly exciting footballer with room to become even better. It didn’t quite turn out that way. Félix showed moments of greatness without ever really grasping it, and after a few years it became clear he didn’t mesh well with Diego Simeone’s approach to the game. Following loan spells at Chelsea, which began with a red card on his debut, and Barcelona, Atletico somehow convinced Chelsea to buy him in a deal worth up to £46.3 million in 2024. He barely played in his second spell at Stamford Bridge and spent the second half of the campaign on loan with AC Milan. Félix now plays with Cristiano Ronaldo for Al-Nassr in Saudi Arabia at the age of 26. A tremendous waste of potential. 1. Kylian Mbappé – AS Monaco to PSG, £165.7mIn 2017, Paris Saint-Germain smashed the world transfer record by signing Neymar from Barcelona for an earth-shattering £200 million fee. Just weeks later they signed Kylian Mbappé from Ligue 1 rivals Monaco for almost £166 million. It was one of the most incredible, jaw-dropping transfer windows of all time. Neymar never quite matched the hype of his record-breaking move, but Mbappé was worth every cent. The forward scored 235 goals in 264 appearances, winning six league titles and four French cups in the process. But Mbappé and PSG couldn’t get over the line in the UEFA Champions League, losing the final in 2020. Ironically, the club have won it twice consecutively since he joined Real Madrid in 2024. Read – 69 classic FPL team names to use ahead of 2026/27See Also – Arsenal’s £128m Vini Jr decision is really about beating JanuaryFollow the Football Faithful on Social Media:Facebook | Instagram | Twitter | YouTube | TikTokThe post The five biggest transfer fees ever paid for teenagers in football history appeared first on The Football Faithful.