Everton have been dealt a double injury blow after Ross Barkley and Ramiro Funes Mori underwent surgery, with the latter expected to miss a minimum of six to nine months.
Argentina international Funes Mori, 26, suffered a torn meniscus while on international duty in March and has now gone under the knife again in Barcelona, meaning he will miss most of the 2017-18 season.
Barkley's future has been the source of much debate following manager Ronald Koeman's insistence he must sign a new contract or face being sold this summer, but the midfielder is now facing four weeks out with a groin problem.