Chelsea are considering a move for Juventus centre-back Matthijs de Ligt, according to reports.
The Blues failed in their pursuit of Jules Kounde in the summer after Sevilla raised their asking price to £68m.
Thomas Tuchel is still keen to bolster his defensive options in an upcoming transfer window, having lost Kurt Zouma to West Ham last month.
Antonio Rudiger and Andreas Christensen are out of contract next summer, and discussions with the former have stalled.
Thiago Silva could also depart the club when his deal expires at the end of the season, when he will be almost 38.
The Netherlands international will not come cheap, though. His release clause stands at £103m, which would make him the most expensive defender of all time.
Juventus are trying to tie De Ligt down to a new contract with a higher release clause.
His current deal runs until 2024 after the former Ajax man signed up for five years at the Allianz Stadium in 2019.
The Dutchman is one of the most highly-rated central defenders in the world, and Chelsea are hoping he will be enticed by the prospect of playing in the Premier League.
De Ligt has already racked up more than 200 senior appearances despite only turning 22 last month.
He could potentially become the centrepiece of Chelsea's defence for a decade or more, but Juventus will do everything they can to retain him.
The Serie A giants have had a slow start to the new season, though, and a failure to qualify for the Champions League could push De Ligt closer to the exit door.
For now Tuchel will be focused on more pressing concerns as he prepares his team to face Manchester City, the Premier League champions, on Saturday.
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