The Dutch beat Belarus 3-1 on Saturday to move onto 16 points from nine matches, three behind Sweden, who sit second in Group A.
Jokes have been made at the expense of head coach Dick Advocaat after he claimed it would be "stupid" to suggest Janne Andersson's side would beat Luxembourg 8-0 on Saturday, only to see that very result play out in Stockholm.
It means Netherlands must beat Sweden by seven goals when the teams meet in Amsterdam on Tuesday if they are to have any hope of snatching a place in next month's play-off round.
Winger Arjen Robben claimed "it isn't going to happen" but Janssen is determined to keep the faith until the bitter end.
"Of course, the chances are very slim, but as long as that little possibility is there, you have to play the game.
"It's a very difficult task, but crazier things happen in football."
Sweden's victory came as something of a surprise given Luxembourg had kept back-to-back clean sheets in qualifying matches, beating Belarus 1-0 in August before holding group leaders France to a shock goalless draw.
Netherlands full-back Daryl Janmaat admits they had hoped for a more spirited resistance from Luc Holtz's side.
"It got to 4-0, 5-0 and they got worse," the Watford man told Fox Sports. "We had hoped Luxembourg could offer something more as opponents."