Chelsea have discovered how much they will have to pay to secure a deal for highly-rated Senegal goalkeeper Edouard Mendy.

Frank Lampard is understood to be keen on the Rennes stopper to put pressure on or replace current no. 1 Kepa Arrizabalaga.

World record signing Kepa was dropped for veteran keeper Willy Caballero towards the end of last season after a series of mishaps.

With Caballero, 38, not getting any younger, despite extending his contract for a year, Lampard will now be concerned about a long-term back up option for Kepa.

It may even be the case that the Blues boss is looking for a more reliable first choice option, and he could sell Kepa if he manages to land a stopper he trusts.

Rennes goalkeeper Edouard Mendy is wanted by Chelsea
Rennes goalkeeper Edouard Mendy is wanted by Chelsea

The man Chelsea have identified to fill that role is Rennes’ Mendy, who kept 13 clean sheets in 34 appearances in his debut season for the Ligue 1 side.

And Sky Sports report that they could land his services for as little as £18m this summer.

It’s claimed that the Blues will put “all their efforts” into securing a deal for Mendy, having failed with an approach for Mike Maignan from Lille.

Mike Maignan has shone at Lille and caught the attention of Chelsea

Maignan, 25, was thought to be Lampard’s preferred choice, but the club’s failed to agree on a price for the France international.

The west London side are understood to have valued Maignan at around £22m, considerably less than Lille’s asking price of £32m.

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Maignan is said to be furious that he was not allowed to discuss a move with Chelsea before linking up with the France squad this weekend's game against Sweden in the Nations League.

Lampard's side return to Premier League action on Monday 14 September when they travel to Brighton.