The Senegalese international will compete with Kepa Arrizabalaga and Willy Caballero for a starting spot at Stamford Bridge.

"I am so excited to be joining Chelsea," said Mendy. "It's a dream for me to be a part of this exciting squad and to work with Frank Lampard and all of his coaching staff.

"I look forward to meeting my team-mates and can't wait to get started."

Chelsea director Marina Granovskaia said: "As soon as Petr Cech and our technical team identified Edouard as the most suitable goalkeeper to complement our existing group, there was only one player we wanted to bring in."

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