You may not have heard of them before the season began, but the chances are the names of Weston McKennie, Jadon Sancho, Dayot Upamecano, Fiete Arp and Kevin Danso are more than familiar to football fans across the world after their impressive debut 2017/18 seasons in the Bundesliga.

bundesliga.com takes a closer look at the five teenagers to have enjoyed breakthrough seasons...

Weston McKennie

Age: 19
Club: Schalke
Position: Defensive midfield
Appearances: 22

Before 2017/18: McKennie joined Schalke from the FC Dallas youth academy in August 2016 and made such an impression in his debut season in the club's Under-19 side that he was soon training with the senior pros. Former head coach Markus Weinzierl was convinced of his qualities to such an extent that he handed the Texas native his Bundesliga debut on Matchday 34, bringing him on as a 77th-minute substitute in a 1-1 draw with Ingolstadt. Schalke went on to confirm that McKennie would be promoted to the senior squad for the next season.

After 2017/18: It was a decision they would not regret. New boss Domenico Tedesco liked what he saw and after making two substitute appearances in the first two matchdays of the campaign, McKennie's next three outings were all in the starting line-up, despite fierce competition from Max Meyer, Bayern Munich-bound Leon Goretzka and Nabil Bentaleb for a place in central midfield.

A fun-loving, laid-back character off the pitch, McKennie is transformed when on it, becoming a hard-running, tough-tackling terrier. "Weston is fearless and he always wants to have the ball, regardless of how tight the situation is," said Schalke sporting director Christian Heidel. "He doesn't just want to go with the flow; he wants to set his stamp on the game." It is fair to say he has done so this term: McKennie has featured in 21 Bundesliga matches (starting 12) ahead of Matchday 34, and would undoubtedly have played more were it not for a knee injury that kept him out of action for six weeks. Oh, and he also scored on his full international debut for the USA in a 1-1 draw with reigning European champions Portugal in November 2017.

Watch: McKennie, Schalke's wonderkid

Fiete Arp

Age: 18
Club: Hamburg
Position: Striker
Appearances: 18

Before 2017/18: Arp has been one of the Bundesliga's worst-kept secrets for a couple of years now. Invited to train with the HSV seniors for the first time in November 2016 by former Hamburg coach Markus Gisdol, who described him as "a massive talent," he underlined his status as one to watch in summer 2017 with five goals and three assists at the FIFA U-17 World Cup, while he received the prestigious Fritz Walter gold medal for his age group – a prize given to German football’s brightest up-and-coming talents. 

After 2017/18: Handed a new contract at the club to fend off interest from a host of European giants, Arp was fast-tracked into the first team and soon made history. At just 17, he became the first player born after the year 2000 to play in the Bundesliga when he made his debut on Matchday 7 against Werder Bremen and also the first millennial to score in Germany's top flight when he found the net against Hertha Berlin on Matchday 10.

He mas made 18 league appearances this term (eight starts) and scored two goals - all of which while juggling his academic commitments as he finishes school. Freed of such restraints next season, the 6'2", quick-fotted forward will be an evern more terrifying prospect. "The lad's got everything, really everything," said Germany Under-21 coach and former Hamburg legend Horst Hrubesch. "I've rarely seen a player who can score a goal out of nothing like he can."

Watch: Arp describes the feeling of scoring his first Bundesliga goal

Jadon Sancho

Age: 18
Club: Borussia Dortmund
Position: Attacking midfield
Appearances: 11

Before 2017/18: Sancho had long been touted as a potential star in England, his performances for Watford's youth team catching the eye of Premier League champions Manchester City, who signed him in summer 2015. He was flirting on the fringes of the first team squad last year, especially after being named Player of the Tournament at the UEFA Under-17 European Championship in May, contributing at least a goal or an assist every game as England finished runners-up to Spain. However, he rejected the offer of a professional contract with the Citizens in favour of greater first team opportunities at Borussia Dortmund, signing on deadline day in August 2017.

After 2017/18: The move soon paid off. Former head coach Peter Bosz, who gave Sancho his professional debut as a substitute away to Eintracht Frankfurt on Matchday 9, was lavish in his praise of the youngster: "He's very young but he's also very talented. I'm really pleased we have him with us." A couple of ligament injuries subsequently limited his appearances, but Sancho still featured in 11 games, making six starts.

Quick, skillful and unafraid to take on his marker, the London native has forced his way into the first team reckoning, often keeping far more senior players like Andre Schürrle and Mario Götze on the bench. He scored his first top flight goal in a 4-0 thrashing of Bayer Leverkusen on Matchday 31, and has also chipped in with a further four assists. "To play for the first team, in front of the yellow wall, is a dream come true," he said. And one that is only just beginning.

Watch: Sancho scored his first goal and claimed two assists against Leverkusen!

Kevin Danso

Age: 19
Club: Augsburg
Position: Centre-back
Appearances: 22

Before 2017/18: Born in Austria to Ghanaian parents, Danso was a striker in Reading’s youth academy in England; a midfielder in Milton Keynes Dons’; and now turns out at the heart of Augsburg’s defence. Standing at 6'3" he is powerfully built and quick on his feet, so it was perhaps inevitable that he would make it as a pro. He joined Augsburg at the age of 14 in January 2014 and was handed his Bundesliga debut towards the end of 2016/17, one of seven league appearances he made that campaign.

Kevin Danso wheels away in celebration after scoring his against Borussia Dortmund on Matchday 24.
Kevin Danso wheels away in celebration after scoring his against Borussia Dortmund on Matchday 24. © imago

After 2017/18: If those were his first baby steps as a professional, 2017/18 was a full-blown sprint for Danso as he developed into first-choice centre-back at Augsburg. He has made 15 Bundesliga outings this term – a number limited only by his absence through injury – while he has scored twice, rescuing 1-1 draws against both Bayer Leverkusen and Borussia Dortmund.

Now also a full international for Austria, Danso has admirers across the Bundesliga. “I have great respect for how he deals with things as a character and he hasn’t lost his humility even though he is a big, beefy player,” said his coach Manuel Baum. Meanwhile, Leipzig striker Timo Werner, who was marked out of the game when the two met on Matchday 22, said, “He’s a colossus!”

Dayot Upamecano

Age: 19
Club: RB Leipzig
Position: Centre-back
Appearances: 39

Before 2017/18: Think of all the attributes you would need to create the prototype centre-back and the player you'd likely come up with is Dayot Upamecano: tall (6'1"), quick, strong, good on the ball and dominant in the air. Those very qualities took him to RB Salzburg in July 2015 and such was his progress that just 18 months later Upamecano was on his way to newly promoted RB Leipzig. He made 12 league appearances in second half of the 2016/17 campaign, becoming Leipzig's youngest-ever Bundesliga player in the process.

After 2017/18: The French defender swiftly went on to demonstrate he was no half-season wonder, carving out a place for himself at the heart of back-line alongside captain Willi Orban and making more league appearances than any other Leipzig defender in 2017/18 (27).

He added goal scoring to his enviable list of abilities in 2018, finding the net twice – including netting the side's milestone 100th Bundesliga goal – in the campaign run-in to earn himself a nomination for the Bundesliga Team of the Season.

Dayot Upamecano has made a huge impact at RB Leipzig both on and off the pitch.
Dayot Upamecano has made a huge impact at RB Leipzig both on and off the pitch. © DFL DEUTSCHE FUSSBALL LIGA / Boris Streubel

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