The in-form New Zealanders have won their last nine one-day internationals and they top the standings in the tournament.
But they are likely to face some of their biggest challenges in their remaining Super Eights matches against Sri Lanka, South Africa and Australia.
"The toughest test is coming up now in these three games, people see these three teams as semi-finalists," New Zealand left-arm spinner Daniel Vettori told a news conference on Wednesday.
"We know it's going to be difficult, but we're almost guaranteed a semi-final spot and we know we can control our own destiny if we win tomorrow."
Fans who were relishing the prospect of Sri Lanka's Lasith Malinga and New Zealander Shane Bond unleashing their express deliveries in the same match will be disappointed to hear that Malinga has been forced out with torn ligaments in his left ankle.
Vettori, though, did not share their sentiments.
"You can see the smile on my face. I'm sure we're all comfortable with that," Vettori said when he was asked how he felt about not having to face Malinga.
Vettori all but promised that Bond would be firing his deliveries at the Sri Lankan batsmen.
"We know Shane's our strike bowler, our marquee player, and what we've tried to do for the last few years is to work around him," Vettori said. "That's been a success, and I don't think we'll change from that."
The seven-week World Cup culminates in the April 28 final in Barbados.
