De Jong was added to the squad on Monday after Dirk Kuyt (hamstring) withdrew, while Robin van Persie (groin) also declared himself unfit.
With Klaas-Jan Huntelaar (knee) and Ricky van Wolfswinkel (toe) also unavailable, De Jong will be given a chance to shine.
The 24-year-old has scored five goals for Ajax in this season's Eredivisie and will be hopeful of continuing his form in his fifth international appearance.
"This is an emergency scenario, but a responsible emergency scenario," Van Gaal told a press conference ahead of the match.
"It will be nice to see how we are going to solve this.
"As a coaching staff, we do indicate that (they need to be ready), but the players have do it themselves on the field."
Following their clash with Japan, Netherlands will face Colombia in Amsterdam on Tuesday.
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