Watford are refusing to part with Abdoulaye Doucouré as Chelsea try to pull off a late deal to bring in the midfield signing Maurizio Sarri wants.
Blues boss Sarri has been adamant that Chelsea need to sign a replacement for Cesc Fabregas, who recently left Stamford Bridge for Monaco.
Doucoure emerged as a possible target ahead of the deadline but Watford have made it clear he is not for sale.
Chelsea, meanwhile, have fended off interest from Paris St-Germain in Willian but have agreed to another loan deal for Michy Batshuayi, according to reports.
It follows speculation that PSG could target Willian as a possible replacement for the injured Neymar.
The Brazilian looks set to stay at Stamford Bridge, while Batshuayi could move elsewhere after failing to impress while on loan at Valencia.
Chelsea have agreed in principle to loan the Belgian striker to West Ham or Real Betis if he chooses to join either.
The Blues would reportedly rather sell Batshuayi to Everton, who cannot take another Chelsea player on loan because they already have Kurt Zouma.
Speaking on Sky Sports News, former Tottenham and England midfielder Jamie Redknapp suggested taking Batshuayi on loan would be a “no brainer” despite his previous struggles.
“I think they need to bring in a striker,” Redknapp said.
“When I think of the great Everton sides they’ve always had a great centre-forward, someone that could lead the line.
“Is Michy Batshuayi the answer? Everyone is trying to unearth this talent that he’s got. He seems to go from one place to another and he’s been sent back from Valencia where he’s been on loan. It didn’t really work out for him there.
“Batshuayi on a loan would be a no brainer. I really think it’s worth getting him in and seeing whether you can get something out of him.”