The Barcelona academy product has shone since leaving the Camp Nou, scoring 14 goals in La Liga - the best by any player in a bottom-half team - for the Costa del Sol outfit.
But such form has made him ultimately impossible to keep for Malaga, who agreed to a €6million (£5.1m) release clause in his contract when they signed him from the Nou Camp club last summer.
Ronald Koeman was spotted at La Rosaleda last weekend watching the 21-year-old forward in person - a final check on a player who came with a glowing recommendation from the club's regional scouts and recruitment chief Steve Walsh.
Newcastle are understood to have made a late enquiry but it was Sevilla who were pushing hardest to rival Everton's interest.
A big contract and an opportunity to potentially be Romelu Lukaku's replacement have convinced Sandro to turn down Champions League football in Seville, while sources close to the forward say he had been assured of "significant" investment in the Everton squad when talks first began.
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