Real Madrid could face expulsion from this season's Copa del Rey after fielding an ineligible player in the first leg of their fourth round clash against Cadiz.

Madrid won the match 3-1, but Russian striker Denis Cheryshev should not have played after he was meant to serve a one game ban after receiving three yellow cards while on loan at Valencia last season.

Cheryshev opened the scoring for Madrid in the third minute of the match.

Osasuna, from the Spanish second division were expelled from the Copa del Rey earlier in the season after also fielding an ineligible player in their third round tie.