The La Liga club's president Jose Maria del Nido expects Toral to complete his move on Tuesday after he quit as Racing Santander boss on Friday.
Toral will sign a one-year contract as Gregorio Manzano's successor with the option of a further year at the Ramon Sanchez Pizjuan.
"Marcelino will be presented tomorrow at noon, God willing," said president Jose Maria del Nido. "Tonight he will come to Seville and dine with me and others."
Toral will have European football to look forward to with his new club.
Sevilla wound up fifth in La Liga to book their spot in the Europa League.