The west London club lost both Antonio Rudiger and Andreas Christensen on free transfers this summer – to Real Madrid and Barcelona respectively – while skipper Cesar Azpilicueta is also believed to be keen to return to Spain.
Thomas Tuchel has identified his back-line as an area that needs significant investment as a result and the club are closing in on a deal for Kalidou Koulibaly.
A fee with Napoli has already been agreed and the Senegal international touched down in London on Wednesday night.
After several changes to their plan for Koulibaly, Chelsea have now decided that he will undergo a medical in the capital on Thursday before flying to the United States to join the rest of the squad on their pre-season tour – either in Los Angeles or the second leg in Las Vegas.
Chelsea are hoping to bring in two more experienced central defenders to join him, with talks well underway to sign Nathan Ake from Manchester City.
Personal terms have already been agreed with the Dutchman – who came through the west London club’s academy – but a fee still needs to be agreed with the Premier League champions.
Chelsea are optimistic of wrapping up negotiations by the end of next week and have also opened talks with Paris Saint-Germain over Presnel Kimpembe.
The French champions want in excess of £50million for the France international, while the Blues also face significant competition from Italian giants Juventus.
While fans may be getting excited by the prospect of signing three such established centre-backs, the triple swoop appears to be bad news for academy starlet Levi Colwill.
According to transfer expert Fabrizio Romano, the 19-year-old is now increasingly likely to leave Stamford Bridge this summer – and most probably on a permanent deal.
The teenager has made it clear he wants to play regular first-team football next season but that will be virtually impossible if Chelsea have Thiago Silva, Trevoh Chalobah, Koulibaly, Ake and Kimpembe all on their books.
Colwill has been taking part in pre-season training with the first-team squad, going on their tour of the USA, but does not appear to have done enough to show Tuchel that he does not need to invest so heavily in the transfer market.
Chelsea were ruthless in offloading young players under Roman Abramovich – with Fikayo Tomori, Marc Guehi and, somewhat ironically, Ake all sold – and that trend looks set to continue under Todd Boehly.
Speaking in May, Colwill was very clear that he would be prepared to leave Chelsea if first-team football was not on offer, saying: ‘For me, playing for Chelsea will always be the main aim right now because it’s my club.
‘But if that doesn’t happen, well then I have to find other ways to progress and become the player I want to be.’
Leicester City, Southampton and Everton are among the many Premier League clubs who would be keen to take Colwill off Chelsea’s hands, either permanently or on loan.
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