Spain defender Gerard Pique is reportedly facing a race to be fit for his side's last-16 clash with Russia on Sunday.
The Barcelona defender has featured in each of Spain's three matches so far at the World Cup, as the one-time world champions finished top of Group B ahead of Portugal.
According to Marca, however, the defender clashed with goalkeeper Pepe Reina in a training session on Saturday and suffered a knock to his ankle.
The news outlet reports that Pique, who was able to rejoin the session shortly after, will still have to prove his fitness for manager Fernando Hierro to consider him in the starting team.
The 31-year-old centre-back has scored five goals in 100 caps for his country.