Peter Fulton hit a solid 83 as New Zealand boosted their chances of qualifying for the World Cup semi-finals with an emphatic 129-run win over Ireland in a Super Eight match on Monday.
The opener's sixth half-century and a rollicking 71-run stand for the eighth wicket between Brendon McCullum and James Franklin helped New Zealand reach a challenging 263-8.
Left-arm spinner Daniel Vettori bagged four wickets as New Zealand dismissed debutants Ireland for 134 to post their sixth successive win in the tournament, including three in the first round.
Defending champions Australia and New Zealand are the only unbeaten sides with eight points from four matches. They are followed by Sri Lanka (6/4), South Africa (4/4), England (2/4), the West Indies (2/4) and Bangladesh (2/4).
"Fulton's innings was important because things were not going too well around him. I guess his 83 held things together and we were able to post a competitive score once we got some hitting at the end," said New Zealand skipper Stephen Fleming.
"Ireland did exactly what we thought they would do. They put pressure on us and we weren't good enough to get partnerships in the middle.
"He (Vettori) did a terrific job. He's not a massive turner of the ball, but his subtleties with pace and variation are very, very good. And he used that to great effect today."
Ireland never looked like threatening New Zealand's total despite an entertaining 75-run stand for the fourth wicket between Kevin O'Brien (49) and brother Niall O'Brien (30). Kevin smashed three huge sixes in his 45-ball knock.
Fast bowler Shane Bond rocked Ireland with two quick wickets in his lively opening spell, removing William Porterfield and Jeremy Bray to eventually finish with 2-18 off five overs.
Vettori and off-spinner Jeetan Patel (2-32) kept non-stop pressure on Ireland, who lost their last seven wickets for 24 runs.
"After the first ten overs, I thought we bowled particularly well. We kept them down until around the 43rd over and then they got on top of us," said Irish captain Trent Johnston.
"It's one thing we've been working hard on (death bowling) but we didn't execute those plans today. All credit to New Zealand. They are a very good team and will be one of the favourites to win this competition."
Earlier, man-of-the-match Fulton's responsible knock and a late flurry of boundaries from wicket-keeper McCullum (47) and Franklin (34 not out) put paid to Ireland's hopes of restricting New Zealand to a modest total.
It was New Zealand's depth in batting that thwarted Ireland who reduced the opposition to 189-7 in the 43rd over before losing their way in the closing stages, with 45 coming in the last three overs.
McCullum's 37-ball knock contained a six in the last over that smashed a window-pane in one of the boxes, while Franklin hit one six and three fours in his 22-ball innings.
Seamer Dave Langford-Smith (2-41), and off-spinners Kyle McCallan (2-35) and Andrew White (2-45) had bowled with discipline to raise Ireland's hopes of containing New Zealand despite Fulton's half-century.
The New Zealand opener regained form with a well-paced innings just when his team-mates had been struggling for runs against Ireland's disciplined seam-spin comination.
Fulton, a middle-order batsman opening the innings in the World Cup, had made only 62 in his last three matches before playing a valuable innings.
New Zealand were not allowed to build a partnership as Fleming (10), Hamish Marshall (16), Scott Styris (10), Craig McMillan (22) and all-rounder Oram (20) all got starts, but none could play a long knock.