The West Indies must seek maximum points in the preliminaries to win the World Cup.

This, says their coach Roger Harper, could be the difference between success and defeat.

Noting that teams will carry forward points - won in the preliminaries - against other teams also advancing to the Super Six stage of competition, he stressed it was crucial therefore to treat each match with utmost seriousness, even if the West Indies earn a berth to the next phase with four early victories.

"It's very important to win every match. I think victories in the preliminary round against teams that go through can help you to secure a place in the semi-finals and just make it a touch easier," noted Harper, speaking to The Royal Gazette yesterday from Port Elizabeth in South Africa, where the West Indies face New Zealand tomorrow.

The Caribbean team have four points from beating South Africa on Sunday and another win would put them in good stead as the Kiwis have already lost to Sri Lanka.

These four sides are expected to battle for the three qualifying spots in Group B. Should the West Indies advance, and triumph against the other teams in their pool who also qualify, they would begin the Super Sixes with eight points.

"It (the points system) ensures that you take every game seriously and you try to see if you can win as many games as possible. They all count," declared Harper.

Despite New Zealand's dismal performance against Sri Lanka, the coach warned that the West Indies could not afford complacency.

"Everyone knows New Zealand are a very competitive team, one that really works hard and plays well as a unit. We are not reading anything into that performance against Sri Lanka.

"They came back very well towards the end of that game and we expect them to play tough cricket and we have to ensure we are ready.

"We see this as a big opportunity for us to press even further ahead and try and cement a place in the Super Six stage."

Harper, who will end a three-year stint in charge of the West Indies after the World Cup, described his players as being "in very good spirits" following their magnificent, three-run upset of the hosts.

Reflecting on the positives of that huge team effort, he praised the batsmen who withstood a poor start to post 278 for five in 50 overs.

"I thought that, from a batting perspective, our patience was really our strength. South Africa bowled very well in the first 20 overs of that game. We lost two early wickets but we stayed calm, showed tremendous composure and our patience saw us through in the end.

"We managed to put together a big partnership with Brian (Lara) and Shiv (Chanderpaul) and then capitalise on it," he said.

"If anything, I thought we could have bowled a touch better at the start of South Africa's innings and we could have been a little sharper in the field."

The explosive return of world record-holder Lara was the perfect filip to a team that has proven a capable One-Day outfit in recent months, noted the coach.

"I think Brian came into the team determined to do well and to make his mark in this World Cup tournament. He batted with great application and the situation really demanded it.

"It was really heartening to see him come through for us like that. I think with the team playing as well as it has been over the last few months - especially in the One-Day format of the game - if we can continue that and get Brian to kick in at the top of his game, as he just did, then the sky really is the limit."

Harper is optimistic that the West Indies can give an even better showing tomorrow.

"We are fully aware of what needs to be done. When we look at our game plan for New Zealand we will discuss some of the errors we made against South Africa and we know we have to tighten up in those areas," he said, adding that the final XI would be picked this evening.

Having suffered through a stage where the team was searching for the right mix of batsmen, Harper acknowledged it's "comforting" to have so many of the top order firing on all cylinders now.

"The strength of a team is its depth and when you know you have quality players from which to choose, it is very reassuring.

"If we have the unfortunate situation of someone becoming injured, we wouldn't have to worry about another person slotting in and getting the job done."