On 27 October 2009, Alcorcón secured the most famous victory in its history after it defeated La Liga powerhouse Real Madrid 4–0 at home in the first leg of its round-of-32 match in the Copa del Rey.
On 27 October 2009, Alcorcón secured a groundbreaking victory by defeating La Liga powerhouse Real Madrid 4–0 at home in the first leg of their Copa del Rey round-of-32 match, which would go down as one of the most significant moments in the club's history.