Barcelona midfielder Sergio Busquets was taken off with what appeared to be a nasty ankle injury in the first half of Wednesday's Copa del Rey clash with Villarreal.

Busquets left the pitch at El Madrigal on a stretcher after Tomas Pina caught the bottom of his right leg in the act of playing a pass that ultimately led to the hosts' equaliser.

Jeremy Mathieu was introduced in his place three minutes before the break, with Barca now facing an anxious wait on a diagnosis after announcing he would undergo tests on Thursday.

Neymar had given Barca the early lead in the match before Jonathan dos Santos levelled to make it 4-2 on aggregate to the visitors.