Ajax boss Erik ten Hag has even suggested Onana could be one of several other players who may leave Amsterdam this summer, mentioning that agreements have been put in place which would allow his star men to move if the right offer came in.
Chelsea have been linked with a number of other goalkeepers as potential replacements for Kepa, including Dean Henderson and Nick Pope.
Jan Oblak is thought to be top of the summer wishlist but Atletico Madrid are unwilling to sell so the Blues would have to trigger the Slovenian’s £110m release clause if they were to pursue a transfer.
Meanwhile, Chelsea are believed to be on the verge of completing a £72m deal with Leverkusen for the signing of Kai Havertz after agreeing personal terms with the 21-year-old earlier this month.