Chelsea have made their fifth signing of the summer after completing a deal for young French defender Malang Sarr.
The 21-year-old, who left Nice this summer following the expiry of his contract, has signed a five-year deal at Stamford Bridge.
The Blues have confirmed Sarr will spend the 2020/21 season out on loan to "provide the chance to gain valuable game time and add to his experience so he will be ready to join our squad".
Sarr arrives with plenty of experience in France, playing over 100 times for Nice and earning the club's young player of the year award.
In a statement, Chelsea director Marina Granovskaia said: "The opportunity to sign Malang was one we could not miss. He is a tremendous prospect and we will be monitoring him closely during his loan period, hoping he will soon be back at Chelsea. We are very happy to welcome him to the club today."
Chelsea have been busy in the transfer window having already brought in Timo Werner, Hakim Ziyech, Ben Chilwell and Xavier Mbuyamba.
Sarr, who has represented France U16 to U21 level, plays primarily as a centre-back but also featured at left-back on occasion for Nice.
Thiago Silva is due to undergo a Chelsea medical in Milan on Thursday - despite last-ditch efforts by Paris Saint-Germain to offer him a new deal.
The finishing touches to an offer have been agreed between Chelsea and the 35-year-old defender in the past 48 hours.
After undergoing his medical in Milan, the centre-back is then expected to fly from Italy to London on Friday to begin a 14-day period of self-isolation before joining up with Frank Lampard's squad.
Chelsea's pre-season preparations have been disrupted, with a number of players in quarantine after returning from their summer break.
A group of the club's first-team squad, including Mason Mount and Tammy Abraham, are following government guidelines on self-isolation.
Chelsea are back in training and building towards the new Premier League season, with Frank Lampard's team facing Brighton at the Amex Stadium on September 14.
Sky Sports News has approached Chelsea for comment.
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The summer transfer window will run for 10 weeks from July 27 and close at 11pm on October 5.
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