Chelsea have rejected an offer from Borussia Dortmund for Carney Chukwuemeka.
The midfielder, 22, spent last season on loan with the German club, who are looking re-sign him for next season.
Dortmund suggested another loan, this time with the option of a £15m permanent move at the end of the campaign, but Chelsea turned the proposal down.
Meanwhile, Enzo Maresca insists Chelsea need to sign a centre-back to replace the sidelined Levi Colwill.
Colwill is out with a long-term knee injury and head coach Maresca wants a signing made before the transfer window closes.
“I think we need a central defender. We are also looking for a solution internally, but the club knows what I think,” said the Italian.
Chelsea do have other options.
As well as Tosin Adarabioyo and Trevoh Chalobah, Wesley Fofana could be contention for Sunday’s opening Premier League game against Crystal Palace and the Blues recentlysigned Jorrel Hato from Ajax for £37m.
Benoît Badiashile, meanwhile, is currently injured but is expected to be fit soon.
But Maresca said: “Benoit is not on the left side. When we build, we build with Levi in the middle.
“Last year we played 64 games – and we played 64 games with Levi and (or) Tosin. Now Levi is out, the only one who can do that job well is Tosin. We have Premier League, Champions League – these kinds of games.
“Hato is a new one and he never played in the middle last season. Can he do that? It’s different.
“Also we have players like Wes and Benoit who, unfortunately, at this moment have some (injury) problems, and this is the reason why I said that the club knows exactly what I think about central defenders.”
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