Yesterday's win over Marcelo Bielsa's impressive Chile side have seen Spain progress to the knockout stages of the 2010 World Cup. Few expected any less from the reigning European champions, yet the manner in which they progressed was less convincing than expected.
A shock loss to Switzerland in the opening game forced Spain to win their two remaining matches. They accomplished that, but not comfortably, and managed to miss more chances than most teams see in two World Cups.
Defensively they were vulnerable, and they were starved of space by two different tactics: Switzerland's deep defending and Chile's high pressure.
These doubts are bad news for a country with a long history of self-destruction at major tournaments. Spain's abundance of talent in midfield and attack have prevented coach Vicente del Bosque from settling on a formation or style of play. If they are to challenge for the Jules Rimet trophy, they will have to sort out a few fundamental issues.
The first question to be resolved is the preferred forward line. Spain have had enormous success over the past four years using both a single-forward and two-forward systems.
The former allows them to play up to four creative midfielders in constant movement. This is the system employed to such devastating effect against Russia and Germany at the end of Euro 2008. It allows Spain to dominate the ball and much of the field, which gives their playmakers the platform to look for the killer pass.
If this system is used, there is the problem of selecting the forward. Fernando Torres is the popular choice to start, but he is just returning from injury and is out of form. David Villa, in contrast, has three goals in the group stages.
A two forward system is more direct, but no less dangerous. The passing abilities of Xavi, Alonso and Iniesta allow Fernando Torres and David Villa to exploit their speed. This system showed how effective it can be against Chile, where Spain were able to score two counter attacking goals.
What this setup delivers in goals, it loses in control. Without the ball Spain are more vulnerable defensively than most teams. Chile were unlucky to go down to ten men so early and had been causing Spain problems until then. The fact that Chile remained dangerous into the second half with ten men will not stave off Spanish pessimism.
The second dilemma facing Del Bosque is at the heart of the midfield. Unlike his predecessor, who used Marcos Senna alone in front of the defense, Del Bosque seems to prefer the combination of Xabi Alonso and Sergio Busquets.
Perhaps it is because neither player possesses all of the skills to replace the Brazilian-born Senna alone. It could also be that the former Madrid manager prefers the security a second holding player provides. Others believe it is because playing Alonso deep allows Xavi to get forward, where he does the most damage.
Whatever the reason, Del Bosque seems committed to it.
The problem lies in the player who must be sacrificed for the second member of the "double pivot" as it is known in Spain. A formation with only four attacking players cannot accommodate the likes of Torres, Villa, Xavi, Iniesta, Silva, Fabregas or Navas.
Aside from the obvious problem of leaving players of their calibre on the bench, there is a tactical problem.
In Euro 2008, the five forward players' movement off the ball allowed them to create the flowing passing moves that broke down opposition defenses. The replacement of a mobile attacking midfielder with a static holding player means there is one fewer attacker for opposition defenders to worry about.
Many blame Spain's difficulties in breaking down Switzerland and Chile on this change. Even former manager Luis Aragones has been openly critical of the double pivot, and Spain's play in general.
The introduction of Fabregas for Torres in the second half against Chile resulted in the best 18 minutes of football Spain have produced so far. That temporary success may be the impetus for a change, as could Xabi Alonso's sprained ankle.
We will not know how Del Bosque reacts until Tuesday, but it is clear that something must be done.
Until these questions are resolved, the doubts hanging over the Spain camp will remain dangerous to their title-hopes.