Chelsea have reportedly made a €50m (£43m) bid for Ajax midfielder Edson Alvarez.
The Blues have already spent in excess of £250m this summer, with the likes of Wesley Fofana, Marc Cucurella, Raheem Sterling and Kalidou Koulibaly all moving to Stamford Bridge.
However, Thomas Tuchel's side remain active in the transfer market and will look to make at least one more addition before the window shuts at 11pm on Thursday night.
According to a report from De Telegraaf journalist Mike Verweij, Chelsea have lodged a 'mega bid' of £43m for Alvarez and the offer is understood to include add-ons.
The report adds that Alvarez has demanded that Ajax hold talks with the Premier League club and he hopes that both parties can reach an agreement for him to move to West London.
Ajax are understood to have already turned down approaches from Rennes and Newcastle United for the Alvarez earlier in the window, but the 24-year-old now wants to leave the club after learning of interest from Chelsea.
A deal for the 58-cap Mexico international to join the Blues could be complicated as the Dutch transfer window closed on Wednesday night, meaning that Ajax are unable to sign a replacement.
Alvarez is not the only Ajax player who is keen to leave the club as the report adds that Mohammed Kudus has been left frustrated at not being allowed to join Everton, and the midfielder has since decided not to take part in training.
After completing the big-money signing of Fofana from Leicester City on Wednesday, Chelsea have now turned their attention to Alvarez as they are believed to be interested in recruiting a new centre-midfielder before the deadline.
N'Golo Kante is set to a spell on the sidelines with a hamstring injury, while Ruben Loftus-Cheek was forced off at half time in the 2-1 defeat at Southampton on Tuesday after pulling his hamstring.
In addition, Mateo Kovacic is yet to start for Chelsea this term as he is still building up his fitness after a spell out with a knee problem.
The like of Conor Gallagher and Billy Gilmour, meanwhile, are facing uncertain futures at Stamford Bridge as both players are attracting interest from elsewhere.
Alvarez, who can operate as either a defensive midfielder or centre-back, has been a first-team regular at Ajax since joining from Club America in 2019.
The Mexican has scored nine goals and provided five assists in 107 appearances for Ajax across all tournaments, and has also won two Eredivisie titles and one KNVB Beker.
Meanwhile, Chelsea are believed to be in advanced talks with Barcelona over a deal for forward Pierre-Emerick Aubameyang, with the Blues prepared to offer Marcos Alonso as part of a player-plus-cash deal.
