Champions League wonderkids: Five best youngsters to keep an eye on in the 2025-26 UCL

The UEFA Champions League is set for its long-awaited return this week with the first 18 league phase fixtures scheduled, bringing with it the drama and excitement that only Europe's greatest club competition can deliver.

For all of the intrigue and anticipation that surrounds the heavyweight clashes, underdog upsets and the pursuit of glory, the tournament's return also offers a platform like no other for the game's most promising young talents to showcase their ability on club football's biggest stage.

In this article, Sports Mole will be looking at the wonderkids tipped to shine in the 2025-26 Champions League season and use Europe's most prestigious competition as a launchpad to superstardom.

While the likes of Lamine Yamal, Joao Neves and Desire Doue are still in the early stages of their careers and firmly fit into this category, they are all already established stars who have lit up the competition with decisive performances in the highest-profile games.

This article instead looks a step behind in that journey - highlighting the emerging wonderkids who are yet to make their mark at this level.

Franco Mastantuono (Real Madrid)

Despite only turning 18 in August, Mastantuono's reputation already precedes him, having been labelled the 'next Lionel Messi', especially after completing a reported £38.5m move from River Plate to Real Madrid during the summer transfer window.

The attacking midfielder has already broken numerous records for his national team, becoming the youngest player to make his debut for Argentina at 17 years and 296 days, and he recently became the youngest player to wear the iconic number 10 shirt at 18 years and 27 days, breaking Diego Maradona's record.

Many expected Mastantuono, who is equally comfortable drifting inside from the right wing or featuring more centrally, would be a rotation option and could struggle for consistent game time at Real Madrid, but the Argentine has already featured in three of their four La Liga matches, including making two starts.

There have been glimpses of the Argentine's immense ability in those games, and while Xabi Alonso may be reluctant to throw Mastantuono straight into the starting team in the Champions League, preferring to ease him in, the teenager is expected to be Real Madrid's next big star and certainly has the talent to make a huge impact in the competition this season.

Estevao Willian (Chelsea)

Another South American wonderkid to have moved to a major European club this summer is Estevao, who joined from Palmeiras after an initial fee of £29m was agreed back in May 2024, with a further £27m in potential add-ons.

The Brazilian has already featured seven times for Brazil's national side, including scoring his first goal against Chile during the most recent international break, while he has also shown extremely encouraging signs in his first appearances for Chelsea this campaign.

Estevao featured in all of Chelsea's first three matches, making two starts, before missing out against Brentford due to illness, and the Brazilian has been one of Enzo Maresca's most promising attackers, including a brilliant performance in their 5-1 victory over West Ham United, which saw the 18-year-old register an assist and pose a constant threat throughout.

Given Estevao's impressive start to the campaign, the Brazilian is expected to play a large part in Chelsea's Champions League campaign, and with his dazzling dribbling ability, rapid change of pace and quality at the final moment, the winger looks set to star for the Blues and show why he is one of the most promising youngsters in world football.

Rio Ngumoha (Liverpool)

Ngumoha had made just one substitute appearance for Liverpool prior to this term, but after a stellar pre-season that saw the winger score two and assist two in four friendly fixtures, the youngster has pushed his way into Arne Slot's thinking.

The Englishman was made to wait for his chance as he remained on the bench in Liverpool's first two competitive matches of the campaign, but Slot showed great trust by turning to the Ngumoha with just minutes remaining as the Reds searched for a late winner against Newcastle United, and the winger certainly did not let his manager down.

Ngumoha needed only four minutes to make the difference, curling in a stunning goal in the 90+10th minute to seal a 3-2 win for the Reds, becoming Liverpool's youngest-ever goalscorer at 16 years and 361 days and the fourth youngest in Premier League history.

Ngumoha has since featured for Liverpool off the bench again as they chased a winner against Burnley, and while the now 17-year-old was unable to replicate his previous heroics, the winger still made a big impact, including a delightful pass across the box to set up a Jeremie Frimpong effort.

The teenage sensation has been included in Liverpool's Champions League squad, making the cut ahead of Federico Chiesa, and while Ngumoha is expected to have limited opportunities, his obvious talent and ability lead us to believe the youngster will announce himself on the European stage at some point this campaign.

Max Dowman (Arsenal)

Another tremendously talented English youngster, Dowman has become one of the most talked about players in English football this season at the tender age of just 15.

For those that pay an interest in youth football, it will come as no surprise that Dowman's talents have translated to the men's game, though even his biggest believers would have struggled to imagine how seamlessly the 15-year-old has made the step up to senior action.

Dowman particularly caught the eye for Arsenal during their pre-season preparations, most notably winning penalties against Newcastle United and Villarreal, while he also consistently posed a serious threat and troubled defenders nearly, or even over, twice his age.

Dowman's penalty-winning exploits continued on his senior competitive debut for the Gunners against Leeds United, when he became the second youngest player in the Premier League's history at 15 years and 235 days - only behind fellow Hale End graduate Ethan Nwaneri, who enjoyed his own breakout season in the Champions League last term - drawing a foul from Anton Stach to give Viktor Gyokeres the chance to make it 5-0 from the spot.

The 15-year-old has been included in Arsenal's Champions League squad following his eye-catching cameos, and should Mikel Arteta award him an appearance before his 16th birthday on December 31, Dowman will become the youngest player and first 15-year-old to ever play in the competition.

Similarly to Ngumoha, Dowman is unlikely to feature heavily for Arsenal, but as he has already shown in limited minutes this season, the youngster is more than capable of competing in senior football, and we fully expect the 15-year-old to make a name for himself in the Champions League this term.

Can Uzun (Eintracht Frankfurt)

Uzun has been talked about as one of the most promising attacking prospects for several years, making his name for 1. FC Nurnberg's youth teams before enjoying a breakout campaign in 2023-24, scoring 16 goals in 30 2. Bundesliga appearances.

Those performances earned Uzun a move to Eintracht Frankfurt in the summer of 2024 for around £9m, and after a solid first campaign, with four goals and one assist in just 669 minutes of Bundesliga action, the attacker has made a fantastic start to the new term.

Uzun has registered a goal contribution in all of Frankfurt's four matches in 2025-26, recording an assist in their 5-0 win over FV Engers in the DFB Pokal first round and managing three goals and two assists in the first three Bundesliga matches, helping the team to fifth in the league with two wins and one loss.

After Frankfurt reached the quarter-finals of the Europa League last season, proving they can compete against some of Europe's top sides, they will be looking to make an impact in the Champions League this time around, and Uzun, who can play as either the starting forward or just behind the striker, is sure to play a big role in any of their potential success.