With just one point separating the Magyars, Turkey and Romania in the race for second spot in Group D, the already-qualified Dutch have a vital role to play.
The Dutch were the first European nation to qualify for next year's World Cup after their 2-0 win over Andorra last month in Group D, but with important ranking points available, the Oranje coach has urged his side to finish its qualification campaign on a high.
The Netherlands takes on second-placed Hungary on Friday as Sandor Egervari's men battle Turkey and Romania for a playoff spot, with just one point separating the three sides with two games remaining.
Hungary got its campaign back on track with a 5-1 victory over Estonia in September but after not winning any of its previous three matches, the team is left fighting to stay in contention for second place.
Facing a team which has sealed qualification may have raised Hungary's hopes of a victory in Amsterdam, but Van Gaal is adamant that his players will be going all out for the three points.
"Outside [Arjen] Robben, [Robin] Van Persie, and [Kevin] Strootman, everyone should still [aim to] prove [themselves] to get a ticket to Brazil and they know that damn well," the former Barcelona boss said.
"These are all test matches. There are plenty of challenges for the players, for me and the staff to prepare for these competitions and go."
The Netherlands has won seven of its eight matches – drawing the other – on the way to sealing a place at its 10th World Cup finals.
The 2010 beaten finalists will be without Van Persie (toe), Gregory van der Wiel (knee), Stijn Schaars (knee) and Jonathan de Guzman (groin), but Leroy Fer and Nigel de Jong are back in the squad.
Adam Szalai has been ruled out for Hungary with flu, but may be fit for the clash with Andorra on Tuesday.