The second leg takes place on Thursday night.
FC Barcelona could face elimination from the Copa del Rey after fielding an 'ineligible player', according to Spanish national daily newspaper
El Mundo.
The report states that Juan Brandariz, better known as Chumi, started the first leg of the cup tie despite being registered with Barcelona's B team, who play in the third tier of Spanish football.
Ernesto Valverde's decision to start the 18-year-old could have severe consequences, as Barcelona could be disqualified from the competition for fielding an ineligible player.
It's not the first time this has happened in the Copa del Rey; during Rafa Benitez's time as Real Madrid manager, Denis Cheryshev played against Cadiz despite not being eligible for selection, resulting in Madrid being chucked out of the tournament.
Levante's failure to file a complaint within a 48-hour window could save Barcelona from elimination, as per
El Mundo's report, which also states that the matter will have to be resolved before the second leg takes place at 21:30 local time.
