Nicknamed 'Lass', the 19 year-old is the subject of a €500,000 offer from Real after an impressive Segunda Liga campaign. His buyout clause is set at €1.5 million.
"I'm crazy about going to Madrid. It would be a dream come true," confessed Lass.
Rayo have rejected Real's opening offer - and warned that Sevilla are also in contact for the youngster.