The Argentina international played 23 league games for Everton last season but sustained the season-ending injury while on international duty in March.

Any hopes the 26-year-old had of returning early next season were dashed, however, after the defender suffered a serious setback during his recuperation.

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"Ramiro Funes Mori has had a problem within his knee and has undergone further surgery in Barcelona which will require prolonged rehabilitation of a minimum of six to nine months," the club said on their website. (www.evertonfc.com)

Everton's Ramiro Funes Mori after being sent off Image credit: Reuters

Everton's injury list also includes midfielder Ross Barkley, who underwent surgery for a groin injury, as well as long-term absentees Yannick Bolasie and Seamus Coleman.

The Merseyside club play their final game of the pre-season tour against Belgium's KRC Genk on Saturday before the first leg of their Europa League qualifier on July 27.

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