Chelsea are still trying to sign Jules Kounde from Sevilla before the transfer deadline, according to reports.
The summer window will close for business at 11pm BST on Tuesday, and Chelsea's business could go right down to the wire.
Thomas Tuchel's side are working on a deal to bring in Saul Niguez on loan from Atletico Madrid.
Their priority, though, is Kounde, who has been linked with a move to Stamford Bridge for several weeks.
The Frenchman, who was left out of the Sevilla team for their match against Elche on Saturday, wants to join the Blues.
Chelsea thought a £43m bid would be sufficient to sign the 22-year-old, but the Spanish side rejected that offer last week.
Sevilla have since increased their asking price, and have reportedly told Chelsea they must trigger the defender's £68.5m buy-out clause.
According to Diario de Sevilla, Chelsea have told Kounde and his agent that they will make one last push to agree a deal.
The report adds that certain members of the Sevilla board are willing to give the green light to the transfer.
Kounde has also put pressure on the club, but other key figures at the Estadio Ramon Sanchez Pizjuan believe Sevilla should retain the centre-back for another year.
Chelsea are running out of time to do the deal, then, and Tuchel will no doubt be frustrated if they are unable to get it over the line.
Kurt Zouma has departed Stamford Bridge, leaving the German with one fewer centre-back in his squad.
The ambition was to replace Zouma with Kounde, and that still might happen - but Chelsea will need to move quickly.
The west London side do still have numerous options at centre-half, including Thiago Silva, Cesar Azpilicueta, Andreas Christensen, Antonio Rudiger, Trevoh Chalobah and Ethan Ampadu.
The latter two are relatively inexperienced at Premier League level, though, and Tuchel would prefer another senior option at the back.
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