Chelsea summer signing Kalidou Koulibaly has 'failed to settle in London' as journalist Simon Phillips makes a concerning behind-scenes claim.

The Lowdown: Koulibaly joins...

The Senegal international put pen to paper on a move to Stamford Bridge last year as owner Todd Boehly attempted to replace the likes of Antonio Rudiger.

Koulibaly signed a four-year-contract worth around £160,000-per-week, bringing plenty of pedigree to west London after years starring for Serie A giants Napoli.

The likes of Man City were previously heavily linked with Koulibaly before he joined Chelsea and Pep Guardiola's side even once listed him as a top target.

The Latest: Journalist makes worrying Koulibaly claim...

Speaking to GiveMeSport, journalist Phillips has made a worrying behind-scenes Chelsea claim involving the African defender.

It is believed Koulibaly has 'failed to settle' in London - a factor which has contributed to some questionable performances under Graham Potter.

Phillips explained:

"I’m told that he’s failed to settle in London, at the moment, and that’s been the biggest problem for him.

“It’s affected his form, his mentality and his confidence. You can see it all on the pitch when he does get picked.”

The Verdict: Concern?

The 31-year-old was a star player for Napoli and Chelsea supporters will be hoping he can get over this momentary adjustment period and display his true form.

After six months in the Premier League, this rumour of Koulibaly still not quite settling in could be quite concerning given the time frame.

However, top players in the past have also taken time to produce their best in Engand - perhaps most notably Portugal international Joao Cancelo, who only became a top-performing regular at City after his first full season in Sky Blue.

Koulibaly could be of a similar ilk as his previous stats and plaudits suggest there is definitely a player in there waiting to emerge. Indeed, former Liverpool and Napoli keeper Pepe Reina even once called Chelsea's centre-back 'extraordinary' and one of the best he's ever played with.

The colossal defender also stood out as one of Napoli's best defensive assets during his last full season - averaging more Serie A blocks and clearances per 90 than any regular (WhoScored).

If Koulibaly becomes more settled over time, Potter may have an imperious central defensive star grow into his ranks.