It's hardly a modern phenomenon thanks to Jean-Marc Bosman's tireless efforts, but more and more high-level players are seemingly allowing their contracts to run down in order to become free agents.
For clubs, acquiring players for nothing (wages notwithstanding) is a hugely enticing prospect given the financial situation for the vast majority of European clubs in the wake of the Covid pandemic.
While the situation is bound to change in the coming months, there's currently an abundance of stellar talent who could be free agents at the end of the 2023/24 season.
Here's the 20 most eye-catching players currently available for nothing come summer 2024...
1. Kylian Mbappe
Current club: PSG
Age: 24
Position: Forward
Will it happen this time?
Kylian Mbappe has more than flirted with the idea of leaving PSG on several occasions, but after yet another transfer saga involving the French superstar failed to result in a move away, it looks as if Mbappe will leave the French giants on a free transfer next summer.
Florentino Perez and Real Madrid will be snooping around, that's for sure.
2. Alejandro Balde
Current club: Barcelona
Age: 19
Position: Defender
The Barcelona left-back's current deal in Catalonia expires next summer, but surely there's no chance he will depart on a free transfer?
Barca are already working on an extension, with Balde likely to sign a new long-term deal at the club after emerging as one of Europe's most exciting young full-backs.
3. Adrien Rabiot
Current club: Juventus
Age: 28
Position: Midfielder
Once frequently chastised by Juventini, Rabiot has slowly built up his reputation in Turin and 2022/23 was undoubtedly his best in Serie A.
The Frenchman has previously been linked with a move to Manchester United, but it's likely that Juve will seek to extend the midfielder's deal, especially if he continues to impress in 2023/24.
4. Piotr Zielinski
Current club: Napoli
Age: 29
Position: Midfielder
The Polish international is one of Serie A's most underrated stars, although his role in Napoli's Scudetto triumph last season saw him increase in popular prominence.
Nevertheless, Zielinksi came close to leaving Naples for the Saudi Pro League in the summer before having a change of heart. It's feasible, however, that he leaves Napoli for nothing at the end of 2023/24.
5. Nico Williams
Current club: Athletic Club
Age: 21
Position: Forward
Securing the services of Nico Williams may well be Athletic Club's primary goal right now. It'd be a detrimental blow if they were to lose him for nothing next summer.
Williams, whose been capped nine times by Spain, has excelled at a senior level to the point where he's no longer recognised as merely Inaki's younger brother.
An extension would at least mean Athletic earn a fair buck for any potential sale.
6. Guido Rodriguez
Current club: Real Betis
Age: 29
Position: Midfielder
The Argentine international and World Cup winner has forged an impressive reputation in Seville, establishing himself as one of the best holding midfielders La Liga has to offer.
Real Betis are currently at risk of losing him for nothing next summer as they're yet to strike a deal over a contract extension.
There's also been talk of Barcelona making a move in January, while Nottingham Forest have also been linked.
7. Presnel Kimpembe
Current club: PSG
Age: 28
Position: Defender
Kimpember suffered a devastating Achilles injury earlier this year and his career at PSG will soon reach a crossroads. It's not yet clear when he'll return to action, and whether the club will risk offering him a new deal.
While the Frenchman was once regarded as one of Europe's premier defenders, PSG are pretty well-stocked in that department and it's unlikely that Kimpembe will swiftly return to his pre-injury level once he returns.
8. Lamine Yamal
Current club: Barcelona
Age: 16
Position: Forward
After breaking into both the Barcelona and Spain starting lineup at the tender age of 16, it's safe to assume wonderboy Lamine Yamal won't be leaving Catalonia this summer for nothing.
But as it stands, the prodigious young talent is available at the end of the season - that's until a bumper new contract lands in front of him, likely with a €1bn release clause inserted.
9. Youssouf Fofana
Current club: AS Monaco
Age: 24
Position: Midfielder
West Ham tracked French international Fofana in the summer before opting to go in a different direction in regards to their midfield search.
Nevertheless, a number of Premier League and other leading European clubs would be wise to consider the 24-year-old next summer should he fail to reach an agreement with Monaco.
The Ligue 1 outfit would be wise to do everything they can to ensure Fofana extends, with their future looking pretty bright with Adi Hutter at the helm.
10. Aaron Wan-Bissaka
Current club: Man Utd
Age: 25
Position: Defender
While Wan-Bissaka is still only 25 and an excellent one-vs-one defender, there's an argument to say that Manchester United need to move on from the English right-back if Erik ten Hag's project is to reach a new gear.
But a new Old Trafford contract could be in the offing, with the Dutchman understood to be open to extending the former Palace full-back's stay.
11. Toni Kroos
Current club: Real Madrid
Age: 32
Position: Midfielder
While Real Madrid have taken several steps to rejuvenating their midfield in recent years, Kroos continues to play at an incredibly high level and there's no doubt that he has more to give in the Spanish capital.
It wouldn't feel right seeing the German line-up in anything but the pearly white of Madrid, but who knows what Carlo Ancelotti and the club's hierarchy have planned.
12. Callum Wilson
Current club: Newcastle
Age: 31
Position: Forward
Wilson quietly enjoyed a fine 2022/23 campaign as Newcastle returned to the Champions League, although much of the talk surrounded the magic of Alexander Isak.
The Swede is the current and future of the Magpies, and there are questions about where 31-year-old Wilson lies in Eddie Howe's project moving forward. A club of Newcastle's ambition may cut ties with the England international next summer.
13. Jorginho
Current club: Arsenal
Age: 31
Position: Midfielder
Signed as a Moises Caicedo alternative in January 2023, Jorginho has proven to be a serviceable option for Mikel Arteta at Arsenal.
However, the summer arrival of Declan Rice will limit his opportunities in 2023/24 and the Italian international will be expected to move on in search of regular minutes at the end of the season.
14. Thiago
Current club: Liverpool
Age: 33
Position: Midfielder
The Spaniard wasn't a part of Liverpool's midfield exodus in the summer, but injuries continue to cripple Thiago's time at Anfield.
The Reds, in all likelihood, aren't going to extend the midfielder's deal beyond its current expiry, with a switch to Saudi Arabia a potential option for the former Bayern maestro.
15. Rafa
Current club: Benfica
Age: 30
Position: Winger
The spritely but savvy Benfica stalwart has been a model of consistency throughout his time in Lisbon, hitting double digits for goals and assists in every Primeira Liga season since 2018/19.
There have been discussions about an extension, but the parties involved are yet to reach an agreement with Benfica slightly hesitant to match Rafa's demands.
16. Mehdi Taremi
Current club: Porto
Age: 31
Position: Forward
The Iranian forward thought he'd be leaving Porto in the summer with just a year left on his deal, but a move to Milan never transpired.
Taremi, for now, remains on Porto's books but there's been little movement in regards to a new deal.
17. Gabriel Barbosa
Current club: Flamengo
Age: 27
Position: Forward
Gabriel Barbosa's previous European venture ended in disaster, but clubs might be tempted by the Brazilian given that he could be acquired on the cheap next year.
His contract at Flamengo expires next December, although any potential suitors will be wary that the striker's output has gradually declined season-on-season since his 25-goal 2019 campaign.
18. Alvaro Morata
Current club: Atletico Madrid
Age: 30
Position: Forward
There's just something about Morata which coaches adore. While he's never been considered among the elite, the Spaniard has built up quite the CV.
His latest return to Atletico was pretty messy after a loan spell at Juventus, but he's started the 2023/24 season in good form and it wouldn't be a surprise if the Spanish club offer him a short-term extension.
19. Alex Meret
Current club: Napoli
Age: 26
Position: Goalkeeper
Great things were once expected of Meret and while he was Napoli's number one during their title-winning campaign last season, the Italian goalkeeper hasn't quite lived up to initial expectations.
Nevertheless, at 26 he's still incredibly young for a goalkeeper and Napoli would be wise to tie him down to an extension rather than letting him leave for nothing.
20. Koke
Current club: Atletico Madrid
Age: 31
Position: Midfielder
Injury woes are continuing to strike the Spanish midfielder, but, like Kroos at Real Madrid, it wouldn't sit comfortably to see Koke suit up in anything but the red and white of Atleti.
Fitness concerns may reduce the size of his new deal, but Los Rojiblancos' commitment to their skipper could be unwavering despite logic suggesting that his wages could be better served elsewhere.
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This article was originally published on 90min as Out of contract in 2024: Football's best free agents at the end of the season.