Chelsea are reportedly in talks with Monaco over the signing of French centre-back Benoit Badiashile.
The 21-year-old joined the Monegasques youth ranks in 2016 and has risen through the academy system to become one of the most highly-rated young defenders in Europe.
Badiashile has already made 135 appearances for Monaco in all competitions, scoring six goals and providing three assists from the heart of defence since becoming a regular in the 2018-19 campaign.
A two-cap France international, Badiashile has struggled with a couple of injuries this season, but he has still managed two goals from 16 appearances in Ligue 1 and the Europa League.
The centre-back will soon enter the final 18 months of his contract at the Stade Louis II, meaning that Monaco could come under pressure to sell in January or the summer if he does not pen fresh terms.
Manchester United were strongly linked with a move for Badiashile over the summer, which failed to materialise, while Barcelona and Manchester City are also said to have been keeping an eye on his development.
Now, The Athletic reports that Chelsea have opened discussions with Monaco over a winter deal after identifying Badiashile as their leading target in the left centre-back area.
The report adds that the two clubs are yet to strike an agreement, but there is a belief that Badiashile will become a Chelsea player for around €35m (£31m) in the coming weeks.
The Blues added to their defensive ranks with the signings of Wesley Fofana and Kalidou Koulibaly in the summer, with the duo arriving to replace Antonio Rudiger and Andreas Christensen.
However, Fofana has been sidelined for the past couple of months with a knee injury, while Koulibaly will turn 32 next year and is not seen as a long-term solution.
Graham Potter's side have been focused on signing up-and-coming starlets since Todd Boehly's takeover, and RB Leipzig's Josko Gvardiol was seemingly their priority for a backline reinforcement.
However, with the Croatia international being lauded as one of the best defenders of the 2022 World Cup, Chelsea have been forced to look elsewhere given Gvardiol's rising price tag.
As well as Badiashile, Potter's side are also said to be tracking Eintracht Frankfurt's Evan Ndicka and Bayer Leverkusen's Piero Hincapie, who played at centre-back for Ecuador at the World Cup but can also feature as an out-and-out left-back.
Chelsea are already said to be on the verge of sealing two youthful signings, with 20-year-old Molde striker David Datro Fofana reportedly already completing his medical ahead of a January move.
The Blues are also believed to have won the race to sign 18-year-old Vasco da Gama midfielder Andrey Santos in a deal that could reach £20m, but the Brazilian teenager's move is not as far along as Fofana's.