There are some big names available on a free transfer in summer 2020 from Europe's biggest clubs if they don't put pen to paper soon. Here are the top ones, with the help of Transfermarkt.
Christian Eriksen (Tottenham)
Tottenham haven't made any ground with Eriksen over a new contract as yet, despite managing to hold onto him over a summer in which Real Madrid, Barcelona and Juventus all showed an interest. The Denmark midfielder would be a massive loss to Spurs and if he doesn't want to commit then a move to Real looks the best bet.
Jan Vertonghen and Toby Alderweireld (Tottenham)
While we're taking about potential losses to Tottenham, the club did well to keep both Vertonghen and Alderweireld on one-year extensions when it looked like both centre-backs would leave. It was incredible that no team went for Alderweireld when he was available for £25m, but now Spurs have a similar issue with the pair to solve.
Nemanja Matic (Man United)
Given how important Matic was to United under Jose Mourinho, it seems odd that Ole Gunnar Solksjaer has kept him out of favour. The Serbian is still only 31, but it's a case of whether United are more keen on youth than experience these days to take up their one-year option on him. Eric Bailly is another who may need new terms, with a two-year option to take up next summer, but his history of injuries might mean United choose to let him go.
Luka Modric (Real Madrid)
Sergio Ramos evidently has a deal until 2021 rather than the reported 2020, but Modric does not and at 33 he could well decide it's time to move on, having almost joined Inter Milan last year. The Croatian is still a world-class player but Real's focus is on the future. Defender Nacho is also out of contract in the summer, with a lack of playing time likely to see him move.
Edinson Cavani (PSG)
Cavani has cut a frustrated figure at PSG behind Neymar and Kylian Mbappe in goals and status. At 32, he will be considering his next move and MLS could be on the agenda with David Beckham's Inter Miami reportedly keen. Arsenal and Manchester United might also be interested in right-back Thomas Meunier, who looks set to move on before his deal expires at the same time.
Dries Mertens (Napoli)
Napoli have a decision to make over Mertens, who is stalling over new terms with Manchester United reportedly interested. The future of another 32-year-old, Jose Callejon, is also up in the air as he turned down a move to Shanghai Shenhua in the summer.
Now that the Callum Hudson-Odoi contract saga has been put to bed finally, Chelsea can turn their attentions to a couple of other wingers whose contracts are up next summer. Willian and Pedro's deals are also expiring, so the club need to act fast unless they want to lose them for nothing.
Mario Gotze (Dortmund)
Forever to be known as the man who scored the winner in the 2014 World Cup final for Germany, Gotze may feel like he has some more to prove. Still only 27, after a failed move to Bayern, links to Liverpool (and former boss Jurgen Klopp) won't go away. But the club are in talks over an extension and Portugal left-back Raphael Guerreiro is another that Dortmund will want to keep.
Ryan Fraser (Bournemouth)
Bournemouth are reportedly ready to offer around £100,000-a-week to winger Fraser to keep him at the club, but Arsenal and Leicester have shown an interest. Fraser is only 25, so the fact he will be a free agent if he can't agree new terms will be very appealing to other Premier League clubs.
David Silva (Man City)
He may be 33, but Silva is still top quality and has already revealed that he will be departing after 10 years. City have another Silva, Bernardo, to replace him but the Spaniard will continue playing and told ESPN FC last year that he would like to end his career playing for Las Palmas, his hometown club on the island of Gran Canaria.