Money in football is just going up and up and up. Be it transfer fees, player wages, ticket prices or TV deals. It's rare you get something for value – let alone nothing – but in just a few months time there'll be a crop of big-name free agents on the market.

Clubs can approach anyone whose contract is expiring in under six months so long as they play outside of that nation to strike a pre-contract agreement and, from June 30, anyone out of contract can move without a transfer fee – so long as they're over the age of 23.

There are hundreds of players who'll become free agents this summer, here are ten of the most high-profile…

Willian

Chelsea forward Willian in Premier League action against Crystal Palace

The Brazilian has rediscovered something close to his best form under Frank Lampard at Chelsea this season. In fact, the 31-year-old has become one of the Blues' leaders and has been captain on several occasions – an indication of his standing at Stamford Bridge.

Long linked with Spanish giants BarcelonaJuventus have also shown an interest in the former Shakhtar Donetsk wideman – Chelsea's policy of only handing one-year deals to players over 30 could come back to haunt them.

The Blues went back on that infamous stance last summer to hand David Luiz a multi-year extension. But that was when they were under a transfer embargo and retaining assets was of paramount importance. With Callum Hudson-Odoi and Christian Pulisic representing the future, Willian might want to explore his options abroad.

Ryan Fraser

The Bournemouth winger was widely regarded as one of the best players outside the Premier League's top six at the start of this season. But the Scot has struggled to replicate his flying form of the last couple of seasons and has found himself relegated to bit-part player in the Cherries' battle for survival.

Reports of interest from Arsenal were not uncommon prior to this season with the 25-year-old – Fraser turns 26 in February – offering a direct and pacey alternative to the Gunners' inside forwards.

This week, fresh reports have emerged claiming Manchester United attempted to sign the diminutive Scottish international in January. If Fraser is to leave the South Coast this summer, you can expect a host of top-half sides to be taking a keen interest, even off the back of a difficult season.

Thomas Meunier

Belgian right-back Thomas Meunier in action for Paris Saint-Germain

The 28-year-old Belgian full-back might not belong in Paris Saint-Germain‘s clutch of world-class superstars but he remains an integral part of Thomas Tuchel's side and the only senior right-back available to the German following Dani Alves‘ exit last summer.

Meunier has made his intention to leave the Parc des Princes clear for some time now and has been linked with moves to the Premier League and Italy with Juventus, kings of the free transfer, just one of the interested parties.

In January, Manchester United reportedly ‘identified' Meunier as the man to replace Ashley Young following his switch to Internazionale. The Red Devils were linked with plenty of players but this was one of the few links which made sense. They will have to act quickly.

Dries Mertens

Napoli's Belgian forward Dries Mertens

One of the most in-demand free agents on the market, Mertens looks set to walk out on Napoli after seven goal-laden seasons when his contract expires this summer. He will be irreplaceable.

The diminutive attacker arrived from PSV as a wide forward but has transitioned into one of the best false nines in European football. The 2016/17 campaign was his piece de resistance, netting an incredible 34 goals from just 46 appearances.

He's recently surpassed the 115 goals Napoli legend Diego Maradona scored during his time the Stadio San Paolo. Interest from the Chinese Super League has been followed by links with Atlético Madrid, Internazionale, Milan, Juventus and, most recently, Chelsea.

Edinson Cavani

Having finally grown tired at being left out of the side in favour of PSG's Quatres Fantastiques, Cavani declared his intention to leave the French capital in January with sporting director Leonardo and coach Tuchel begrudgingly respecting his decision.

However, a move did not materialise and he will instead become a free agent in June after seven years with the Ligue 1 giants. Atlético Madrid were thought to be closest to El Matador but could not agree on a price with les Parisiens for their all-time leading goalscorer of 198 goals.

Former club Napoli have also shown an interest – and could have a vacancy up top if the aforementioned Mertens leaves – while Chelsea and Manchester United are keen.

Nemanja Matić

Manchester United midfielder Nemanja Matić

For a long time last summer it looked as though the powerful Serbian midfielder would be reunited with Antonio Conte, his former boss at Chelsea, at Inter. However, a deal could not be struck and Matić stuck around at Old Trafford.

There's little doubt the 31-year-old's powers have waned and Ole Gunnar Solskjær prefers a more mobile midfield comprised of Frederico and Scott McTominay. Bruno Fernandes‘ arrival won't help Matić's case either.

However, in recent weeks the former Chelsea and Benfica enforcer has given a timely reminder of why José Mourinho paid £40million to sign him from the Blues three summers ago. He was even nominated for the club's Player of the Month award for January. Could a shock renewal be on the cards?

Mario Götze

Borussia Dortmund midfielder Mario Götze

Hero of Germany's 2014 World Cup triumph, the intervening years have been unkind to the Borussia Dortmund attacker who has had to overcome illness, injury and a controversial move to Bayern Munich which simply didn't work out for him.

Back at Borussia Dortmund, the side he left in 2013 to sign for Die Roten, things have improved but the magic of his first spell at the Westfalenstadion has proved impossible to replicate.

Reports in Germany say Götze, who is still only 27, will leave BVB for the second time this summer – though sporting director Michael Zorc has denied this. The versatile attacker claims a move to Liverpool is ‘always an option' while Jürgen Klopp – his coach at Dortmund – is in charge at Anfield.

José Callejón

The Spanish forward has never quite been the star of the show at Napoli but with 79 strikes in seven seasons for the Partenopei, he should not be short of interest if he becomes a free agent.

Now 32, the five-time Spain international would provide versatility – he can play on the flanks or through the middle – as well as pace and goals to any prospective buyer.

This summer looks set to mark the end of an era at Napoli as the great side of Carlo Ancelotti and Maurizio Sarri is broken up. A return to Spain looks likely with former club Espanyol one potential destination. Everton, now coached by Ancelotti, have inevitably been linked too.

Jan Vertonghen

Tottenham Hotspur defender Jan Vertonghen

Tottenham Hotspur have already secured one half of their long-standing central defensive partnership with countryman Toby Alderweireld inking a new agreement earlier this season. But Vertonghen's future remains up in the air.

Now 32, the former Ajax defender remains one of the best in the Premier League, despite reacting badly to being hooked against Southampton in the FA Cup. His agent later said Vertonghen “still wants to achieve great things” with Spurs.

However, there have been plenty of rumours linking Vertonghen with a move away from North London and a potential reunion with ex-Spurs team-mate Christian Eriksen at Inter. Napoli and Ajax are also said to be interested.

Blaise Matuidi

Juventus midfielder Blaise Matuidi

Having survived last summer following the arrivals of midfield duo Aaron Ramsey and Adrien Rabiot, the 32-year-old Frenchman could find his time at Juventus is up this summer instead.

The Bianconeri are one of the most active pursuers of free agents in European football and they will be reluctant to lose one of their own for nothing. In fact, reports in Italy claim Juve have the option to extend the World Cup winner's contract by another year.

Conversely, other reports claim Real Madrid's Casemiro is already being lined up to replace Matuidi.

Transfers