Chelsea are among the clubs to have been offered the chance to sign Atletico Madrid midfielder Saul Niguez on loan.
Saul was part of Diego Simeone's title-winning side last season but will be allowed to leave the club this summer.
The 26-year-old has made more than 300 appearances for Atletico since breaking into the first team as a 17-year-old in 2012.
He has also played 19 times for Spain but was left out of their Euros squad this summer.
Manchester United have been watching the midfielder, along with Eduardo Camavinga from Rennes.
Chelsea head coach Thomas Tuchel said on Sunday he was happy with his squad. However, he may look to sign another midfielder after allowing Billy Gilmour to join Norwich City on loan.
Tuchel already has a number of midfield options including Jorginho, Mateo Kovacic and N'Golo Kante.
Chelsea are trying to find clubs for midfielders Tiemoue Bakayoko, who is close to joining AC Milan on loan, Ross Barkley and Danny Drinkwater.
Chelsea are in talks with defender Antonio Rudiger's representatives over a new contract.
The Germany international has entered the final year of his current deal but told Tuchel he remains fully committed to the Premier League club.
However, Rudiger wants to assess all his options before deciding on the next step of his career.
Chelsea were in the process of extending the 28-year-old's contract last October ahead of allowing him to leave on loan when Tottenham, PSG and AC Milan were all interested.
A loan move did not materialise after Rudiger opted to stay and fight for his place, and he has become first choice since Tuchel took over from Frank Lampard.
He can sign a pre-contract agreement with a foreign club in January, with Real Madrid and PSG both interested.
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