According to reports in Spain, one of three generators at the stadium exploded after a severe electrical accident which left three people injured - two seriously - but repairs were able to be made, allowing both countries to train after a delay.
The game against Belarus is scheduled to kick-off on Friday at 10pm local time.
Jorge Perez, secretary general of the Spanish Football Federation, says thoughts are with those injured in the incident.
"What worries us is the state of the two people seriously injured," Perez told Marca.
Reports say police have said the explosion was the result of an accident which left the stadium without electricity, but repairs were being carried out.