​Breaking into the full international team can be a long, hard slog. 


You have to pay your dues for the Under-21s - 46 times if you're as unlucky as James Milner - play the waiting game and grasp the opportunity with both hands when it finally arrives. 


Failure to do so can result in a return to the youth setup with potential tails between legs - something one player on our list knows all too well.


Here's 90min's list of Europe’s best young stars who still play for international Under-21 sides.


Phil Foden (England Under-21s)

Phil Foden

If Pep Guardiola's press conferences are anything to go by, Phil Foden is one of world football's brightest young midfielders. If you use minutes on the pitch as a metric, then the 'Stockport Iniesta' will be waiting a long time to catch up to the Spain legend of that rather generous nickname. 


The problem for Foden is that minutes make the midfielder, something Gareth Southgate has been clear about in his squad selection. At 19, there will be admiring glances to both Declan Rice (20) and James Maddison (22) who have qualified as full England internationals by completing their own Premier League apprenticeships. 


While Maddison and Rice can boast 47 and 73 appearances respectively, Foden sits on just 22 - the majority coming as a substitute. Southgate has earmarked the midfielder as one for the future, but progress cannot happen without minutes for ​Manchester City.


Ansu Fati (Spain Under-21s)

Ansu Fati

When your career trajectory begins by breaking Barcelona records before you can legally buy a beer, you'd probably expect your international career to gain momentum at a similar pace. 


That's exactly what's happened for Guinea-Bissau-born Ansu Fati, whose eligibility to represent La Roja was only cleared in September. Since, it has resulted in two appearances for Spain's Under-21s. 


Fati became the Blaugrana's youngest goal scorer by notching against Osasuna at the age of just 16 years and 304 days, and by adding an assist in the same game he became La Liga's youngest player to achieve both feats in a fixture. 


Moise Kean (Italy Under-21s)

Bioty Moise Kean

If Moise Kean had hit the ground running at Everton then there's an argument that he could have been leading the line in Roberto Mancini's surge for Euro 2020. Kean made his debut for the senior side at this time last year, following it up with two goals in two March 2019 qualifiers against Finland and Liechtenstein.


Sadly, ​the Toffees are yet to witness the great potential Kean showed at Juventus and he finds himself back in the Italy Under-21 squad, after failing to score a Premier League goal thus far. 


Rafael Leao (Portugal Under-21s)

FIFA U-20 World Cup Poland 2019"Portugal U20 v Argentina U20"

Eight goals in 24 Ligue 1 appearances was enough to convince Milan to pay Lille a reported €30m for Leao's signature this summer. 


Unfortunately for both Leao and the Rossoneri, this has yielded just one goal in nine Serie A appearances. The Portugal striker boasts a similar record for his nation's Under-21s, scoring just once in seven.


Milan could do with the ball hitting the back of the net as much as Leao, with just 11 goals in 12 Serie A matches a huge factor in why they sit 14th in the league table. If the young Portuguese can start firing for both, he'll find himself much closer to the senior squad.


Odsonne Edouard (France Under-21s)

FBL-EURO-2021-U21-SVK-FRA

Celtic supporters will be more surprised that their latest young talent hasn't been picked off as of yet. After 14 goals in 28 Scottish Premiership appearances in 2018/19, Edouard has already notched eight in 11 this season - goalscoring form that has continued for France Under-21s.


Edouard is currently the top scorer in Euro 2021 qualification and has scored six times in just three fixtures, hence his inclusion here. 


The issue lies in France's embarrassment of attacking riches, but with ​Oliver Giroud now 33 and Wissam Ben Yedder and Antoine Griezmann approaching 30 the time for succession planning will soon come. A full international call up isn't as crazy as it sounds.


Dani de Wit (Netherlands Under-21s)

Dani De Wit

AZ Alkmaar mean business in 2019/20, second in the Eredivisie table and just two points behind their Europa League group leaders Manchester United with two games remaining. Dani de Wit has been at the heart of their progress, pulling strings and linking play from a number ten position.


Beyond the obvious candidates of Frenkie de Jong, Donny van de Beek and Georginio Wijnaldum, Ronald Koeman's side are lacking a creative influence to introduce from the bench. 


An issue that has been apparent in recently laboured performances against Northern Ireland (twice) and Belarus. Dani has already shown that he has De Wit (sorry) to do so for Alkmaar, perhaps it's time Koeman gave him a chance...


Eduardo Camavinga (France Under-21s)

FBL-FRA-U21

Bossing the midfield battle against PSG at just 16 was always going to catch the eye, but that 2-1 victory for Rennes catapulted Eduardo Camavinga into the global footballing consciousness.


Didier Deschamps' decision to draft Matteo Guendouzi into the senior squad opened the door for Camavinga to make his Under-21 debut this week, and the 17-year-old will be hoping for equally rapid progression to a full call up.


Linked to both ​Manchester United and Barcelona in recent weeks, the future appears to be very bright for the latest in France's production line of exciting midfielders. 


Antonio Marin (Croatia Under-21s)

If links to Manchester City were enough to earn a place in the full Croatia squad, Antonio Marin would have said Doviđenja (Croatian for goodbye) to the Under-21s a little while ago. 


The Citizens have been keeping an eye on Dinamo Zagreb's teenage winger for months, notably since he featured against their U-19 side in Champions League action. 


Contracted until 2024, Dinamo will be hopeful of hanging on their young talent for at least the foreseeable future.