Vicente del Bosque has a selection headache as his side cannot afford another slip up.
David de Gea Spain have no shortage of talent in this department, and both De Gea and Pepe Reina could handle the step up if called upon. Despite a minor injury doubt, it may well be the Manchester United player of the year who is given the nod, after proving his increasing maturity and reliability in an excellent season at Old Trafford.
Cesar Azpilicueta (Full-back)
The vastly improved Chelsea defender could not have done much to change the outcome of the Netherlands game, but the natural left-back never seemed comfortable playing on the right of Spain's back four. He could not prevent the continuous threat of Daley Blind, who ended the night with two assists.
Juanfran One of many in-form Atletico Madrid players not to be given a start, the experienced Juanfran was an ever-present figure for the Primera Division winners. His exceptional performances leave him well equipped to make a World Cup debut, and the right-back would be suited to dealing with league rival and Chile star Alexis Sanchez.
Sergio Ramos (Centre-back)
The Champions League winner and holder of over 100 caps is seen by many to be a guaranteed starter at the heart of Spain's back four. A stuttering performance against the Netherlands, though, culminated in Spain conceding five goals, and Ramos appeared out of touch with his partner Gerard Pique and the rest of the backline.
Javi Martinez Bayern Munich's versatile €40m man is used to being deployed either in midfield or defence, and he may be the change needed to sort out Spain's problem of conceding goals. Part of a Munich side which romped to the Bundesliga title, Martinez would be a competent and reliable option if asked to step into Spain's shaky back four.
Sergio Busquets Solid yet unspectacular, the Barcelona midfielder is reliable but lacks the entertaining style associated with many of his teammates. Despite his consistent selection over recent years, Del Bosque may opt for a younger, more exciting player to pair with the experienced Xavi in an attempt to give Spain's midfield an injection of energy.
Koke The 22-year-old Atletico Madrid midfielder, dubbed 'the new Xavi' would be the obvious choice to step in if Del Bosque decides to make a change in midfield. The young Spaniard had an exceptional season, racking up 13 assists to help his side to the title, whilst scoring the vital goal in the semi-final win over Barcelona in the Champions League.
Diego Costa Was not the worst of the Spanish players against the Netherlands, but questions still remain about whether he fits into a Spanish side which has gained much of its recent success without a centre-forward. The crushing defeat may convince Del Bosque to switch back to the old ways and drop Costa for the pivotal game against Chile.
Cesc Fabregas The newly signed Chelsea midfielder would have no problem slotting into the team with which he has gained so much success. Rather than trying to force Costa into the side and stunting the creativity of his midfield in doing so, Del Bosque could instead utilize Fabregas, and try to recreate the formula that has brought him so much success.