The soccer 2020-21 season is getting into the defining stages, with the top European leagues reaching their last rounds, while the UEFA Champions League and the Europa League are moving closer to the finals as well. Even though it is a moment in which the race for the title heats up, the push for International competitions berths rises and the relegation fight intensifies, teams also have to think beyond their current games.

Despite the attention that any soccer campaign requires, clubs start thinking about the next year way before it begins. The players' contracts are one reason why that occurs. Those whose deals expire in July are enabled to sign for any other team six months earlier and to avoid that happening teams need to act fast.

As the end of the season will be taking place in a couple of months, several superstars may become free agents this summer, with their contracts running out at the end of June. Here, we'll break down the best of them, placing them in a lineup, with the information regarding their maket values provided by TransferMarkt. Check out who are those amazing players.

Gianluigi Donnarumma - (Goalkeeper)

Gianluigi Donnarumma has only 22 years of age but his amazing experience at such an important team like Milan makes him look like a much older goalkeeper. He appeared for the first time with the Rossoneri's being a 16-year-old and went on to hold onto the starting role for the next years. The Italian keeper amassed 243 matches, impressive numbers for a player with his age.

However, his time with Milan may be coming to an end soon. Donnarumma's contract expires on June 30, 2021, and unless he signs a new deal before that date, it would turn him into the best free-agent goalkeeper ahead of the 2021-2022 season. His market value is €60 million.

Elseid Hysaj - (Right-Back)

The right-back's contract with Napoli will come to an end at the end of the season. He looks like the best candidate for this position in free agency, after featuring for more than 200 games for the Serie A team. The Albanian defender can also perform at the left-back, and he can deliver both a solid defense and a threat in offense joining the attack.

His market value is tagged at €14 million, so bringing him in for no cost at all would be huge. There aren't many other outstanding options in his position, and Hysaj looks like the best prospect for a free transfer this summer. 

Sergio Ramos - (Centre-Back)

The Spain national team and Real Madrid's legend is among the most interesting players to enter free agency at the end of the season. Sergio Ramos' contract runs out on June 30, and after 16 seasons, which included multiple achievements, he may leave Los Blancos to pursue another challenge in the final years of his career.

One of the best defenders - if not the greatest - in the world, Ramos would be the best signing for any team that completes the move without paying any transfer fee at all. Even though his market value is stated to be €14 million, mainly due to his age, this defender has been ruling the game for a long time and remains one of the best at his job.

Jerome Boateng - (Centre-Back)

The German's deal with the mighty Bayern Munich is set to be over at the end of this season, which in case that it finally happens, would enable a world-class defender for a free transfer. Jerome Boateng is turning 33 this year, but he would still be a huge boost for any interested candidate.

As he became an older player his market value went down to €10 million, but there's a huge difference if his signing could be made paying only his salary. Boateng still has at least a couple of years left to shine at the top level, let's see who will be the lucky ones to take advantage of that.

David Alaba - (Left-Back)

Frequently linked with Real Madrid in the last transfer windows, David Alaba is the other great option that will be available for a free transfer this summer. The Austrian had a huge development in his game and performed as a central back lately, being a solid piece at the back of Bayern's incredibly successful team

Unlike the other defenders on this lineup, Alaba's market value is high, being €55 million. As he can provide at different positions of the defense and only has 28 years of age, he is a big name for the upcoming season. Will he finally make a permanent move to Madrid?

Georginio Wijnaldum - (Center Midfielder)

The Dutch became a key piece at Liverpool's midfield, asides from creating unforgettable memories with the Reds. The Champions League and Premier League champion earned an important place in Jurgen Klopp's side in a difficult battle for a starting role against other great players. 

However, compatriot Ronald Koeman has been trying to sign him for Barcelona ever since he started to be in charge of the Cules. With only a few months remaining on his deal with Liverpool - it expires on June 30 - Wijnaldum could be making a huge step in joining Koeman at the Blaugranas.

Luka Modric - (Center Midfielder)

Luka Modric's time with Real Madrid could be over at the end of June, after extremely successful seasons that included Champions League and La Liga trophies, among many others. Despite his 35 years of age - to become 36 in September - the Croatian hasn't lost his talent at all and remains an incredible midfielder.

And bringing him in for no transfer cost at all would be a perfect move. With several recognitions, such as The Best award under his belt, Modric would be the perfect fit for any team that can afford him in summer.

Julian Draxler - (Offensive Midfielder)

Many players have a lot of talent but struggle to show it. Julian Draxler is one incredibly gifted star that couldn't earn a place in PSG's starting lineup, despite he proved to have what's necessary for it. The German's contract with the Parisian side will run out on June 30, and it may give him a deserved opportunity to bounce back in his career.

Due to his latest performances, many teams maybe wouldn't be keen to invest so much money in him, but for free, it would make a lot of sense going for it. Just remembering the player he used to be with Schalke 04, Wolfsburg, or even in some games with Paris, could be enough for trusting in Draxler. 

Lionel Messi - (Right-Winger)

If his contract with Barcelona is finally over at the end of this season, he would be the most desired free agent without a doubt. Arguably the greatest player in the world, Messi's fantastic spell with the Catalans may be over in a couple of months, with his deal set to expire on June 30. His future is one of the most thrilling topics ever since he almost left the Blaugranas before the 2020/21 season. He ended up staying for one more year, but it may have been Messi's last dance with the Cules.

Unless he puts pen to paper to a new contract, the Argentine superstar is going to have multiple offers over the table for the next season. The 33-year-old had suffered from all the setbacks he and Barcelona faced over the recent years, and this summer could be crucial for a change in his career

Sergio Aguero - (Striker)

While other players are still uncertain whether they'll continue with their current teams or not, El Kun already knows he won't stay with Manchester City. Both parties have announced the Argentine's contract wouldn't be renewed after June 30, and the striker is already linked with multiple important teams.

Although he struggled with injuries in the last seasons, the 32-year-old remains one of the best strikers in the world, despite he has to overcome the physical issues that cursed him lately. Aguero has wonderful goals and breathtaking performances under his belt, and with a market value of €25 million, the one who signs him for free will be very lucky

Memphis Depay - (Left-Winger)

With 27 years of age and his contract with Olympique Lyon running out on June 30, Memphis Depay looks like a very interesting option for a free transfer. His market value is reported to be €45 million, and the stage of his career couldn't be better. 

The Dutch forward impressed over the last seasons but still couldn't make a move to a more important team from the region. Like it happened with Wijnaldum, Koeman wanted to sign him soon after arriving to Barcelona. Will he fulfill that dream at the end of the season? It seems like the perfect moment for it, but there will probably be many competitors interested in Depay.