Rennes goalkeeper Edouard Mendy is undergoing a medical with Chelsea as he prepares to join the club, Blues manager Frank Lampard says.

The Senegal keeper, 28, will compete with the £71m Kepa Arrizabalaga, the club's record signing.

Kepa was at fault for Liverpool's second goal in the 2-0 Premier League defeat on Sunday, which was described as "a clear mistake" by Lampard.

"We have brought Mendy in for that competition," Lampard said.

"I don't know what benefits in the long run, football is in your hands. Competition is a regular thing. It's in everyone's hands to get into the squad."

Kepa was dropped last season after errors, including in the FA Cup final, where the 25-year-old was replaced by second-choice goalkeeper Willy Caballero, who is 38.

Caballero will start the Carabao Cup tie against Barnsley at Stamford Bridge on Wednesday, although Lampard added that he made that decision before the Liverpool game.

Chelsea had an earlier bid rejected for Mendy, who made 25 league appearances for Ligue 1 side Rennes after joining from Ligue 2's Reims in 2019.

Last season for Rennes, Mendy kept nine clean sheets in his league appearances, compared to Kepa's eight cleans sheets in 33 Premier League appearances.

Mendy's save percentage was 76.3% and he conceded a goal every 114 minutes. Kepa's save percentage was 53.5%, conceding a goal every 63 minutes.

However, Kepa's passing accuracy was 79.7% compared to Mendy's 70.1%.

It is understood Mendy will not replace Kepa but with Caballero turning 39 later this month, the club wants a younger challenger to their current number one.