Premier League clubs boast some of the finest academies in the world.
Manchester United and West Ham are just two of the sides that have spent decades churning out future superstars.
Of course, not all youngsters who are lucky enough to play for a top team at youth level go on to stay with the club.
In many unfortunate cases, they don't make it in professional football at all. For others, they make their names elsewhere.
That means the coaches, mentors and teammates who got them where they are today are often forgotten.
So here at GIVEMESPORT, we're on a mission to change that.
We present to you 21 players whose youth careers may come as a surprise.
Loris Karius - Man City
What?! Way before he was watching Liverpool's Champions League dreams crumble through his hands, the on-loan stopper spent two years at Manchester City. They appear to have been unconvinced by him as he returned to Germany with Mainz, where he started his senior career.
David Beckham - Tottenham
Spurs hoped the future England star would sign a professional deal with them but were told he was "Man United mad". And as we know, that's exactly where he ended up.
Aaron Cresswell - Liverpool
Liverpool won't lose too much sleep over it now that they've got Andy Robertson at left-back. The West Ham man was born on Merseyside and was released by the Reds at the age of 15.
Harry Kane - Arsenal
Arsenal fans love to mock their rivals over the infamous pictures of Harry Kane in a red shirt. The reality is being rejected by the Gunners spurred him on to become the player he is today and his old employers must wish they'd had a bit more foresight.
Fabrice Muamba - Arsenal
Muamba enjoyed his best years at Bolton Wanderers, where he sadly retired early in 2012 after suffering a heart attack on the pitch against Tottenham at White Hart Lane. But it had all begun at Highbury, where he had first joined up for Arsenal in 2002.
Ryan Giggs - Manchester City
Giggs' career could have panned out very differently as he could also have played for England, not Wales. The thought of him in a City shirt might turn United fans' stomachs, but in the end he was known for his...erm, loyalty. To Manchester United.
Fabio Borini - Chelsea
Borini is best remembered for a relatively underwhelming spell at Liverpool. After leaving Bologna in 2007, he actually first came to England to play for Chelsea.
Adrien Rabiot - Manchester City
The volatile Frenchman rocked up to Manchester in 2008 but lasted less than a year. Even as a youngster, he played for seven clubs in 11 years which was perhaps a sign of things to come.
Ryan Shawcross - Manchester United
The centre-back wasn't deemed good enough for United and has instead enjoyed a decent career at Stoke City.
Robbie Savage - Manchester United
Savage is unfortunate in that he's always going to be compared to his contemporaries with whom he won the FA Youth Cup in 1992. While he was nowhere near their level, he's spoken openly about the learning experience of his time at Old Trafford.
Jadon Sancho - Watford
Sancho's story as the Manchester City wonderkid who tried his luck at Borussia Dortmund is well known. It didn't start at City, though. The 20-year-old played for Watford between 2007-2015.
Gareth Barry - Brighton & Hove Albion
Barry made over 300 appearances for Aston Villa after joining in 1997 from Brighton, having spent six years on the coast.
Jamie Vardy - Sheffield Wednesday
It's well-known that Vardy won the Premier League after starting out as a non-league striker. Before that, as a youngster he spent a year at Sheffield Wednesday.
Tom Ince - Liverpool
Ince has had a solid career as a professional but couldn't follow in his Dad's footsteps at Liverpool.
John Terry - West Ham
Terry is not *quite* the one-club man he's made about to be. There was that short loan spell at Nottingham Forest and as a youngster, he was also on West Ham's books for four years. His last year there coincided with Frank Lampard.
Adam Lallana - Bournemouth
Lallana rose to prominence on the South Coast but with Southampton. Bournemouth also deserve credit for his development there before he joined the Saints in 2000.
Jermain Defoe - Charlton
Part of the reason West Ham were so furious when Defoe joined Tottenham was that he had been 'one of their own'. Yet he spent two years at Charlton before linking up with the famous Hammers' Academy.
Kieran Richardson - West Ham
Richardson, on the other hand, is a player whose rise in the early 00s was put solely down to Manchester United. What many forget is that he was born in Greenwich, London and spent time at West Ham first.
Quinton Fortune - Tottenham
Fortune, of course, hailed from South Africa originally. Between 1991-95, he played for Tottenham at youth level and evidently enjoyed his time in the UK, as he later returned for a better remembered stint at Manchester United.
Stan Collymore - Wolves
Collymore scored some iconic goals for Nottingham Forest, Liverpool and Aston Villa. A man made in the Midlands first showed his abilities inside the box at Walsall and Wolves.
Nile Ranger - Southampton
'Where did it all go wrong?' is a question commonly asked of Ranger, but not 'where did it all start?' The striker swapped ends of the country by beginning at Southampton but then making his breakthrough at Newcastle.
Wait, what? Many of these spells have been lost in the midsts of time.
Even when a player isn't deemed ready for the first team and let go, they can go on to prove their doubters wrong elsewhere.
Or perhaps, in some cases, the academies were right about them all along...
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