Keane missed just eight Premier League matches in his debut season on Merseyside and having a strong, established central defensive partner alongside him should help the four-cap player to return to his best form and possibly force his way back into the England set-up.
Zouma subsequently missed almost one season of football before he made his return to the pitch.
The French global spent last season out on loan at Stoke City but couldn't prevent them from being relegated from the Premier League and he's now facing an uncertain future back at Chelsea under Maurizio Sarri. And, Manchester United and Everton are interested.
According to The Times, Everton are now on the brink of completing a deal for the French defender. Mourinho has signed only three players this summer - Fred, Diogo Dalot and Lee Grant - and if this deal goes through, it appears he finally has reason to smile.
The Toffees significantly bolstered their squad on transfer deadline day with the arrivals of Bernard, Andre Gomes and Yerry Mina, but their business is not yet done, with a temporary move for Zouma in the pipeline.
The deal for Zouma was also expected after a deal sheet was submitted, but it took until Friday afternoon for confirmation, with the Frenchman becoming Everton's seventh signing of the summer.