Lionel Messi, Sergio Aguero, Georginio Wijnaldum, Sergio Ramos and David Alaba top the list of European players that will be out of contract by the end of the season.

We have researched through the European leagues and make a list that could possibly make up a starting IX of biggest stars and brightest prospects available for free when their contracts expire this summer. 

Goalkeeper

Gianluigi Donnarumma has been plying his trade as the No 1 stopper at AC Milan for five years, but is only 21 years old and will be available for free when his contract expires at the San Siro this summer.

If he has the longevity of compatriot Gianluigi Buffon, the Italy international could have another 20 years or more in top-flight football, which bodes well in market value for potential suitors.

Defense 

Real Madrid captain and talisman Sergio Ramos also looks increasingly likely to the leave the club when his deal ends in July after 16 years at the club and the 34-year-old is linked with Manchester United.

Sergio Ramos looks set to leave the Bernabeu this summer.

David Alaba will also be on the radar for Premier League clubs after 12 years at Bayern Munich and would offer a huge boon for value at just 28 years old - with a wealth of international experience and versatility to boot.

Dayot Upamecano is Bayern Munich's top target but depends on David Alaba leaving.

Additional value is available in the full-back positions with Napoli right-back Elseid Hysaj and Paris Saint-Germain left-back Juan Bernat up for grabs this summer. Both aged only 27, the pair can also play in a variety of positions.

Midfield

Paris Saint-Germain winger Angel Di Maria (32) slots into a wide midfield role, with Memphis Depay (26) down the opposing flank. Both somewhat flunked during spells at Manchester United but have hit form since switching to Ligue 1.

Things did not work out for Memphis Depay at Manchester United but the Netherlands international has been in fine form for Lyon in Ligue 1

Talent available for free in the central midfield spots are defense-minded kingpin Georginio was Wijnaldum (30) whose new contract agreement reached a stale mate with Liverpool alongside Marseille and France international Florian Thauvin (28).

Attack

Arguably the greatest forward on the planet could be snapped up for free in July, with Lionel Messi (33) and Sergio Aguero (32) in the final months of current deals.

Messi’s transfer request was rejected by Barcelona last summer but his contract situation is never far for the headlines: the latest instalment saw details pertaining to his wages leaked and splashed across the papers.

Meanwhile, this summer will mark Aguero's 10-year anniversary at Manchester City, having notched a club-record 256 goals in that time - but injuries have blighted this campaign.

This summer looks set to offer a raft of world-class potential free agents, with the likes of Fernandinho, Julian Draxler, Luka Modric, Eric Garcia, David Luiz, Lukasz Fabianski and Olivier Giroud also among the options.

  Manchester United are likely to trigger a one-year extension to Edinson Cavani's current short-term deal, while Crystal Palace Mamadou Sakho, Jeffrey Schlupp, Andros Townsend, Christian Benteke, Patrick van Aanholt and Wayne Hennessey could leave the club for nothing.

Other notable potential free agents include Hakan Calhanoglu, Theo Walcott, Ryan Bertrand,, John Lundstram, Danny Rose, Danny Welbeck, Jack Wilshere, Andre Ayew, Eric Maxim Choupo-Moting, Kevin Gameiro, Adam Reach and Andy Carroll.