Real Madrid midfielder Isco has been ruled out of the Madrid derby after being diagnosed with appendicitis.

The reigning Champions League winners did not put a timescale on the 26-year-old’s recovery, but he will definitely miss Saturday’s clash with arch rivals Atletico following surgery on Tuesday afternoon.

The former Malaga man is expected to be out for around four weeks and is also a doubt for next month’s El Clasico with Barcelona at the Nou Camp.

Isco has been a mainstay in Los Blancos’ team since Julen Lopetegui replaced Zinedine Zidane as head coach in the summer, featuring in each of the seven matches in all competitions and has scored two goals in the process.

Lopetegui, speaking at a press conference ahead of Wednesday’s La Liga clash at Sevilla, said: “He had pain this morning and has to have an operation. Hopefully everything goes well and he recovers as soon as possible.

“We wish him a speedy recovery and we’ll think about the solutions and those who can play because we have the utmost confidence in them.

“He’s about to undergo surgery and we hope he returns as soon as possible to full fitness.”