Real Madrid have fielded an ineligible player in their Copa del Rey tie against third-tier side Cadiz, which could result in the La Liga club being disqualified from the competition.

Denis Cheryshev, who spent last season on loan with Villarreal, had a suspension carried over from the previous campaign for an accumulation of yellow cards in the 2014-15 competition.

The Russian played the first half of the match and opened the scoring before being substituted shortly after the restart, while Borja Mayoral, who was sent off in the Copa del Rey Juvenil last season, was included in the substitutes, despite reportedly also being suspended.

According to reports in the Spanish media, Cadiz will have to make an official complaint before 2pm tomorrow in order for the Spanish football federation to investigate the infringement.

Last season, Osasuna were disqualified in similar circumstances.