The transfer window is open across Europe's top leagues so there's no better time to look at some young talent, aged 23 or younger, who could make a real impact.
The likes of Arsenal's Bukayo Saka, Brighton's Moises Caicedo, Barcelona's Gavi, Bayern Munich's Jamal Musiala and AC Milan's Rafael Leao are all world-class players that fit the age requirement, but are far too expensive for most clubs to sign.
So we've put together a Best XI of under-the-radar players from the Big Five leagues in Europe, in a 4-3-3 formation, who could be available for a relatively modest fee.
*All estimated market values taken from Transfermarkt.
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English Premier League
By Jon Molyneux-Carter
GK: James Trafford, 20, Manchester City (€2.5m)
England's goalkeeper at the ongoing European Under-21 Championships, Trafford spent last season on loan at Bolton and has yet to make a first-team appearance for City. Burnley and Sheffield United are fighting it out to sign a player whose reliability, reflexes and distribution make him stand out. A future England No. 1?
LB: Lewis Hall, 18, Chelsea / England (€10m)
An incredible versatile player who can fill in at left wing or central midfield, Hall made nine Premier League appearances for the senior Chelsea side last season. With his dynamic runs and neat control, the teenager also has a fine range of passing and is confident enough to drive forward while also managing his defensive duties.
CB: Levi Colwill, 20, Chelsea / England (€30m)
After a fine spell on loan at Brighton, Colwill is ready to make the step and play regular senior minutes. Will he get a chance back at big spending Chelsea? If not, a move will be needed for a player who has all the attributes to be a major star. Commanding at the back, his positioning, speed and leadership make him a tough opponent. The left-footed defender has great vision, passing and technical skills, so it would a shame to see him wasted on the bench.
CB: Illya Zabarnyi, 20, Bournemouth (€20m)
The highly rated Ukraine centre-back was already being compared to some of Europe's best when he moved to Bournemouth in January, and he didn't disappoint. Dominant in the air and strong in the tackle, Zabarnyi has a big future and it's likely to be at a larger club than Bournemouth.
RB: Tino Livramento, 20, Southampton (€25m)
After moving to Southampton from Chelsea's academy, Livramento burst onto the scene in the Premier League in 2021 but then missed over a year of football following a cruciate knee ligament injury in April 2022. The England U21 defender is an attack-minded full-back and his powerful running and good crossing make him stand out as one to watch. Newcastle are reportedly keen to take advantange of Southampton's relegation and seal a deal.
CM: Stefan Bajcetic, 18, Liverpool / Spain (€13m)
A superb passer who can also win the ball back, Bajcetic is technically excellent and his composure in possession is impressive for one so young. Forcing his way into the Liverpool side last season amid their injury crisis, he played 11 times in the Premier League and four times in the Champions League, which shows how much Jurgen Klopp rates him. But can he hold down a place among the new arrivals at Anfield?
CM: Carney Chukwuemeka, 19, Chelsea / England (€15m)
Chukwuemeka made 14 appearances in Chelsea's awful campaign last season, but only two as a starter. A box-to-box midfielder of immense potential, he is a classic No. 8 and his ability to carry the ball in midfield and make clever runs sees him share some traits with senior England star Jude Bellingham. An €18m signing from Aston Villa in the summer, he hasn't really kicked on and it feels like a move would do him good now that Chelsea are signing more players.
AM: Luke Harris, 18, Fulham / Wales (€500,000)
An attacking midfielder with an eye for goals, Harris made the breakthrough into the senior Fulham side last season and has been tipped for the top. His vision and finishing are impressive, with his desire to get into the box and good runs from deep causing havoc for opponents. A product of the Jersey FA Centre of Excellence, he could have chosen any of the Home Nations for international football but opted for Wales.
FW: Cole Palmer, 21, Manchester City / England (€10m)
Such is the talent on show at City, it's testament to Palmer's ability that he has broken into the first team already. A left-footed winger who plays on the right, Palmer likes to cut inside and shoot on his stronger foot, much like teammate Riyad Mahrez. However after a frustrating year, a loan move is likely, with 19-year-old Oscar Bobb reportedly in contention to replace him in the squad.
FW: Callum Hudson-Odoi, 22, Chelsea / England (€15m)
At one point when he first broke into the Chelsea team, it seemed as if Hudson-Odoi would be a superstar. The winger's pace and dribbling skills marked him out as an attacking threat, but he was never able to maintain the consistency he needed. A loan spell to Bayer Leverkusen last season saw him provide one assist in 14 Bundesliga games. He needs a reset.
ST: Evan Ferguson, 18, Brighton / Ireland (€30m)
Brighton's best kept secret is no longer a secret as he bagged 16 goals in 34 games last season to thrust himself into the spotlight. With two goals in six games for the Republic of Ireland since making his debut in November, Ferguson is only going to go from strength to strength. An archetypal modern striker, he is flexible enough to hold up play, or run in behind the defenders, while he also drops deeper to pick up the ball and combine with his midfield. His movement is exceptional and he also looks completely at home in the Premier League, so it's no wonder the likes of Man United and Tottenham are watching him.
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Spanish LaLiga
By David Cartlidge
GK: Arnau Tenas, 22, Barcelona / Spain (Free)
The 22-year-old is now a free agent but was a regular for Barcelona's reserve side, keeping 15 clean sheets in 26 appearances last season. As you'd expect given he came through the La Masia academy, he's adept with his feet but also has solid basics. A star for Spain in the ongoing U21 Euros, he could be a great addition for any side.
LB: Juan Miranda, 23, Real Betis / Spain (€7m)
After leaving Barcelona for Real Betis in June 2021, Miranda has finally found some stability. He's been a regular for Betis at full-back and has also been featured for Spain at the U21 Euros. A pacey, technically gifted full-back, he has shown the ability to balance attack and defence well.
CB: Jon Pacheco, 22, Real Sociedad / Spain (€6m)
Ball-playing centre-backs are in demand these days, but Pacheco is old-school. He's a no-nonsense, solid defender who excels in the physical side of the game to win duels and regain possession. Real Sociedad's academy has produced another real talent. He's also yet another to have impressed with Spain at the U21 Euros.
CB: Arnau Martinez, 20, Girona / Spain (€15m)
Able to play either centre-back or right-back, Martinez had a fantastic 2022-23 season with Girona. He's strong in the tackle and tough for opponents to beat, but also a gifted passer and dribbler with the ball at his feet. Linked with many top clubs around Europe, he is able to dictate play from the back.
RB: Ivan Fresneda, 18, Real Valladolid / Spain (€15m)
Fresneda recently completed his debut season in LaLiga, but not once did he look out of place. The 6-foot defender has a rangy physique, is adept in dispossessing opponents and stopping attacks, while he has shown plenty of technical quality going forward as well. Barcelona, Arsenal and Borussia Dortmund are all reportedly interested in signing him.
CM: Aimar Oroz, 21, Osasuna / Spain (€15m)
The Osasuna youngster performed superbly last season to help his club finish seventh. Oroz's main role in central midfield was to win the ball back and intercept passes from opponents, but he also linked well with the attack and chipped in with three goals and six assists.
CM: Rodrigo Sanchez, 23, Real Betis / Spain (€8m)
Real Betis have a history of producing gifted young midfielders -- including the likes of Fabian Ruiz and Dani Ceballos -- and Sanchez is the latest. He's a live wire in attacking midfield with plenty of speed and skill, but while he generally keeps things simple in midfield, he is known for bursting forward with the ball at his feet.
CM: Samuel Costa, 22, Almeria / Portugal (€5m)
One of only two non-Spanish players in this LaLiga list, Costa shone last season for Almeria. A tough-tackling, hard-working midfielder, he can feature in front of the defence to offer protection but also has the ability to drive the ball forwards through midfield.
LW: Alex Baena, 21, Villarreal / Spain (€20m)
Baena shot to prominence in his breakthrough LaLiga season with six goals from 35 games, and is an all-action attacker who can play on the wing or at the top of the forward line. Quick, skillful and smart, he likes to make clever runs behind the defence to create space. There's a lot to admire about his game and Baena is the sort of player clubs crave to add some attacking verve.
RW: Gonzalo Plata, 22, Real Valladolid / Ecuador (€5m)
An exciting winger with pace to burn and a wide range of skills, Plata is the sort of player that gets fans off their feet with his ability to drive at opponents and get into danger areas. A long list of European clubs are reportedly lining up to sign him following Real Valladolid's relegation.
CF: Sergio Camello, 22, Atletico Madrid / Spain (€10m)
A pure No. 9 striker if there ever was one, Camello thrived on loan for Rayo Vallecano and scored seven goals in all competitions. A hard-working front man who can press the opposition defence, he has a natural eye for goals and links to the Premier League have continued to emerge.
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German Bundesliga
By Tor-Kristian Karlsen
GK: Noah Atubolu, 21, Freiburg / Germany (€3.5m)
With Freiburg No. 1 Mark Flekken joining Brentford this summer, the scene is set for the Germany U21 international to compete with new arrival Florian Muller for the starting spot. Still to make his Bundesliga debut, Atubolo is an athletic, imposing goalkeeper with excellent reflexes.
RB: Joe Scally, 20, Borussia Mönchengladbach / United States (€12m)
Over the course of two seasons, the United States international has become one of the most trusted members of the Gladbach side. Scally is a force at both ends of the pitch, always ready to provide width going forward, and hardly ever runs out of steam. His physicality renders him useful in winning duels and he plays with admirable energy and focus.
CB: Marton Dardai, 21, Hertha Berlin / Germany (€3.5m)
The son of the Hertha manager and club legend Pal, he has built his reputation climbing the ranks of Germany's national youth teams. Though his introduction to senior club football coincided with relegation last season, the left-footed Dardai is a stylish, composed centre-back who can also deputise in midfield.
CB: Noah Mbamba, 18, Bayer Leverkusen / Belgium (€3m)
The highly rated Belgian was signed by transfer-savvy Leverkusen for a nominal fee in January. Equally comfortable in front of the defence as he is in the middle of it, Mbamba excelled for Club Brugge at youth level and was given his first-team debut at the age of 16. Mobile and strong with either foot, he's able to bring the ball into midfield.
LB: Luca Netz, 20, Borussia Mönchengladbach / Germany (€6.5m)
Physically imposing and with a cultured left foot, the Germany U21 defender provided three assists for Gladbach last season. Expected to occupy a starting slot next season, Netz is a committed tackler (more than three tackles per 90 minutes) and reads the game well.
DM: Eric Martel, 21, FC Cologne / Germany (€9m)
Though predominantly a defensive midfielder, the Germany U21 international can comfortably fill in as a centre-back too. A tenacious ball winner and dominant in the air, Martel tends to keep his distribution simple. Consistent and reliable, he's already an important first-team member at his club.
CM: Arne Engels, 19, Augsburg / Belgium (€7.5m)
Another talented Belgian who's been an ever-present since making the leap from Club Brugge's development side to first-team action in the Bundesliga since January. Versatile, quick and with an excellent work ethic, Engels can excel in any midfield role. Positive in his passing, he strikes the ball well from distance and set pieces.
CM: Enzo Millot, 20, Stuttgart / France (€7m)
Millot enjoyed a positive debut season in the Bundesliga after joining from AS Monaco last summer. Technically gifted and an excellent dribbler, the midfielder frequently drives into the box with purpose and energy (3.5 touches in the opponent's box per 90 minutes.) He proved decisive with two goals in last season's relegation playoff against Hamburg that secured their topflight status.
FW: Julien Duranville, 17, Borussia Dortmund / Belgium (€8.5m)
A speedy winger whose trickery, dribbles and acceleration make him extremely unpredictable. Hugely efficient in tight spaces, he was given his debut in the final Bundesliga game against Mainz that ended in a 2-2 draw and denied them the title. But he impressed a lot in 28 minutes. Don't be surprised if the €8.5m January signing from Anderlecht has a breakthrough season.
FW: Jakub Kaminski, 21, Wolfsburg / Poland (€12m)
Kaminski wasted no time in making an impact following his €10m summer transfer from Lech Poznan by scoring three goals at the tail end of the season. He likes to cut inside from the left onto his right foot, is comfortable on the ball and takes up smart positions in the final third. Already a full senior international for Poland, he made four appearances at the 2022 World Cup.
CF: Nelson Weiper, 18, Mainz / Germany (€5m)
Arguably the most exciting teenage centre-forward in Germany, Weiper was introduced to first-team football last season after his tremendous goal-scoring exploits at youth level. The 18-year-old target man, who netted twice in nine Bundesliga games, backs up his fine link-up play with a powerful physique and first-class finishing with either foot.
Italian Serie A
By Tor-Kristian Karlsen
GK: Marco Carnesecchi, 22, Atalanta / Italy (€13m)
Having spent three seasons on loan at Cremonese as a first choice (he already has over 100 games at professional level), the Italy U21 international is likely to return to Atalanta this summer to compete with Juan Musso for the No. 1 spot. Carnesecchi initiates the play well, with good vision and distribution, and he is not afraid of coming out to claim crosses.
RB: Wilfried Singo, 22, Torino / Ivory Coast (€12m)
A nonstop presence down Torino's right side, the dynamic Ivorian is hard to beat in defender and always prepared to progress the ball or find positions to cross further forward. Singo is an invaluable first-team performer but has been linked with a move to AC Milan.
CB: Lorenzo Pirola, 21, Inter Milan / Italy (€8m)
An old-fashioned centre-back, Pirola excels at the basics of defending and has done well on loan at Salernitana. More suited to playing in a low block rather than in a possession-heavy or high-pressing side, he gets in the way of shots, hassles opponents and approaches every duel with maximum commitment. He regularly receives praise for his outstanding mentality too.
CB: Caleb Okoli, 20, Atalanta / Italy (€10m)
Born in Italy to Nigerian parents, Okoli is almost unbeatable in sprint duels and is perfectly suited to playing in a high defensive line. Though he can improve his work on the ball, he has already shown a maturity beyond his years and rarely makes unnecessary fouls or rash interventions.
LB: Fabiano Parisi, 22, Empoli / Italy (€10m)
Another full-back who looks ripe for a move to a bigger club (Juventus and Inter Milan are reported to be keeping tabs on him), Parisi performed well for his country at the U21 Euros in a wing-back role. Comfortable on the ball and happy to join the attack, Parisi crosses well from deep positions, regularly beats his marker and his high football intelligence allows him to make smart runs into space.
DM: Samuele Ricci, 21, Torino / Italy (€20m)
After making his way through Italy's national youth sides, Ricci was rewarded with two senior caps toward the end of last year. Equally capable of circulating possession from deep in midfield or being given a licence to roam forward from a box-to-box role, the dynamic, refined and tactically astute 21-year-old already plays like a seasoned pro.
CM: Fabio Miretti, 19, Juventus / Italy (€15m)
One of the highlights of a troubled season for Juventus was the emergence of the tidy, hard-working and technically gifted box-to-box midfielder. Full of purpose and intent, Miretti is one of the most positive passers in Serie A, always looking for a forward option to find teammates. Diligent in his pressing and eager to win the ball back, Miretti is among the most promising midfielders to emerge from the Turin club over the past decade.
CM: Tommaso Baldanzi, 20, Empoli / Italy (€15m)
Baldanzi followed up on his breakout season in Serie A by being one of the main players in Italy's run to the FIFA U20 World Cup final last month. Sporting a technical profile not far removed from a throwback Italian trequartista, the 5-foot-7 midfielder is brilliant at finding space and his skill on the ball allows him time to make clever, penetrative passes.
FW: Lazar Samardzic, 21, Udinese / Serbia (€14m)
With only one Serie A season under his belt, the Berlin-born Serbia international already ranks among the league's most incisive attacking midfielders. Habitually finding space in the final third, Samardzic is a constant threat with an extraordinary left foot that can see him finish from distance and facilitate assists.
FW: Matias Soule, 20, Juventus / Argentina (€4m)
The Argentine dealt well with his introduction to senior first-team football last season as he recorded 12 Serie A appearances. With his creativity, dribbling skills and appreciation of quick interchanges, Soule -- who typically appears as an inverted playmaker from the right wing -- possesses all the skills to impact matches.
CF: Sebastiano Esposito, 20, Inter Milan / Italy (€3.5m)
Having made his first-team debut for Inter at just 17, Esposito has not progressed as much as expected and spent the past three years on loan at five different clubs. He strikes the ball exceptionally well and can beat opponents with his neat footwork, so it could only be a matter of time before he starts producing consistently at the highest level if given the chance.
French Ligue 1
By David Cartlidge
GK: Lucas Chevalier, 21, Lille / France (€10m)
Despite his tender age, the goalkeeper was an ever present figure for Lille last season. Indeed, he impressed so much that he was handed the No. 1 spot for France at the U21 Euros and Leeds United's Illan Meslier was relegated to the bench. Chevalier is quick off his line and boasts incredible agility. Man United have previously been linked with him.
LB: Bafode Diakite, 22, Lille / France (€10m)
Something of a centre-back/full-back hybrid -- a role which is popular at the moment -- Diakite has excellent physical and technical attributes for a defender. Quick, good in one-vs.-one situations and a threat in the air, he has a high ceiling to develop.
CB: Castello Lukeba, 20, Lyon / France (€25m)
Mobile and positionally smart, the left-footed Lukeba continues to progress well with Lyon and shone for France at the U21 Euros. He has shown himself to be comfortable in a high-line defence and makes calculated decisions at the right times. Chelsea, RB Leipzig and Tottenham have all been linked with him.
CB: Isaak Toure, 20, Marseille / France (€6m)
Toure impressed while on loan at Auxerre from Marseille and, while he is not the quickest of defenders given his height (6-foot-8), he's dominant in the air. Clever in his positional sense and able to play in either a back three or back four, Toure is mature for his age.
RB: Vanderson, 22, Monaco / Brazil (€20m)
The Monaco full-back is an energetic presence on the pitch and can also be featured as a winger. Not only is he quick, but he is also a good crosser of the ball and supports the attack well. Not flashy in possession, he keeps things simple and has appeared on the radars of Barcelona and Man United in the past.
CM: Eliesse Ben Seghir, 18, Monaco / France (€18m)
Already, the 18-year-old has shown an ability to control the team from midfielder despite his age. He is often found in a second-striker role, playing off the front line and linking attacking moves with his quick, smart passing and ability to dribble. One of the big future prospects from Ligue 1.
CM: Muhammed Cham, 22, Clermont / Austria (€6m)
A left-footed No. 10, the Austria international can also slot in as a winger. An explosive player who can receive the ball and burst away from opponents with sudden acceleration, he has good technical skills and has surely outgrown his surroundings.
CM: Enzo Le Fee, 22, Lorient / France (€20m)
Le Fee is a bundle of energy in midfield, preferring to play in a box-to-box role and use his playmaking abilities. Blessed with technique and vision, how he receives the ball between the lines then moves it on has been notably impressive. He has caught the eye of many Ligue 1 fans purely for how enjoyable he is to watch.
LW: Desire Doue, 18, Rennes / France (€15m)
A true flair player, Doue is another success story for Rennes and shows his personality when he plays. The 18-year-old is an entertainer at heart, full of skills and tricks designed to shake up opponents. Most comfortable as an attacking midfielder, he can also crop up on the wing too.
RW: Lois Openda, 22, Lens / Belgium (€35m)
It's difficult to nail down a set position for Openda, such is his desire to roam across the forward line. Always looking to dribble and drive directly at opponents, he uses his upper-body strength to shake off tackles and is a hard worker with high fitness levels. RB Leipzig and AC Milan have reportedly shown interest, with clubs from the Premier League also taking note.
CF: Elye Wahi, 20, Montpellier / France (€35m)
One of the sensations of last season's Ligue 1, Wahi produced 19 goals and six assists in 33 games for a mid-table Montpellier team. With the ability to hold up the ball and bring others into play, but also with strong finishing, he is close to being the complete striker. Arsenal and Wolves have been the two clubs most notably linked.