Malo Gusto has reportedly arrived in for his medical ahead of his move to , with the Blues to pay €30m (£26.3m) plus add-ons.
It is believed that but the 19-year-old will not be coming straight to Stamford Bridge.
Gusto will instead stay with Lyon for the rest of the season and will link up with his new team-mates over the summer.
The teenager was due to feature for Lyon in their Ligue 1 clash against Ajaccio on Sunday but will now now miss that game in order to complete his medical, according to in France.
France U21 international Gusto has made 15 appearances for Lyon this term and has played a total of 54 games since making his debut in the 2020-21 campaign.
He is being brought in as back-up for Reece James, who has suffered injuries on a worryingly regular basis.
James is now fit again after the two knee injuries he has suffered this season and may return in Chelsea’s next fixture, at home against Fulham on February 3.
Gusto will become the seventh player Chelsea have bought this month, having already brought in Benoit Badiashile, David Datro Fofana, Joao Felix, Andrey Santos, Mykhailo Mudryk and Noni Madueke.
There could still be a move for a midfielder to come before the transfer window shuts next week, with the Blues linked to the likes of Moises Caicedo, Enzo Fernandes and Amadou Onana.
Chelsea have already spent a whopping £468.6m on players since American owner Todd Boehly took control from Roman Abramovich in the summer.
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