Netherlands coach Louis van Gaal is pondering the big question ahead of his team's next match against Australia: should he tinker with a winning formula?
Van Gaal's decision to play a system based on five defenders against Spain was a tactical masterstroke as the Dutch humiliated the defending world champions 5-1 in Salvador in their Group B opener.
Preparing for the World Cup, Van Gaal hinted he might revert to the traditional Dutch 4-3-3 system against an Australian team whose defense can be tough to break down. The Netherlands also played a 4-4-2 formation in a tune-up match against Wales, a decision based on how Van Gaal believes Australia will play when they meet Wednesday in Porto Alegre.
So which is it going to be?
Midfield playmaker Wesley Sneijder, for one, comes from the "if it ain't broke, don't fix it" school. (Also read: Could have beaten Spain by 8 goals, says Van Persie)
"I would say 5-3-2 to continue building for the rest of the tournament," he told the official Netherlands supporters' site OnsOranje.nl.
If players already know which system they will play, they weren't letting on after training Sunday.
"Ask the coach," Daley Blind told reporters. "We're preparing well for the match against Australia and we'll hear it from the coach."
The coach didn't talk to the media Sunday and the training session at the Dutch camp gave no clues.
Blind trained apart from the main group, saying he has a minor knee irritation, but stressing that he is fit to play on Wednesday. (Related: Dutch can improve on Spain Rout, says Van Gaal)
Sneijder may get his wish.
Van Gaal played the 5-3-2 system against Spain because the European and world champions are renowned for their quick-passing, attacking style of play.
The Dutch master tactician wanted to defend solidly and then hit Spain on the counterattack, a plan that worked to perfection as first Robin van Persie and then Arjen Robben latched onto long passes from Blind to score and turn the match around after their team had gone behind to a Xabi Alonso penalty.
In the second Group B match, Australia will de desperate for a win after conceding a stoppage-time goal in a 3-1 loss to Chile in their World Cup opener. That could play into Dutch hands if they adopt the same system as against Spain and punish Australia with swift counterattacks.
Midfielder Nigel de Jong said the Dutch camp is still enjoying its stunning win against Spain that delivered a measure of revenge for Spain's World Cup final win four years ago, when Andres Iniesta's extra-time goal decided the match.
But De Jong repeated the mantra of the coach and senior players ever since the final whistle ended the Spain match.
"The atmosphere's fantastic. How can it not be? ... But at the same time it's just one game in the group," he said. "We didn't win nothing yet."