Chilwell and Mendy set to handed their first start for the Blues in the London Derby on Tuesday night.
Chelsea signed 28-year old goalkeeper Edouard Mendy from Rennes for an estimated £22 million last week.
The Senegal international is deemed to become Chelsea’s No.1 goalkeeper following struggles from world-record signing Kepa Arizzabalaga.
Ben Chilwell who joined in a £50m move from Leicester City is also expected to make his first start for the Blues on Tuesday.
“Mendy and Chilwell are in the squad tomorrow,” Lampard confirmed.
“They are fit and we will see if they start or not.
“Ziyech and Pulisic are not far away but they are still in a recovery phase. It is too early for them both.”
“It is all very positive from the early signs and interactions [with Mendy]. Just as a man on the training pitch.
“He has settled very well in the first few days and we have made him feel welcome as always. It is a competition.
“He is a good goalkeeper and we know a lot about him. We will see how we go.”
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