Nathan Astle hits out (Getty Images).

Click here for full scorecard
Click here for Super Sixes standings
Click here for photo gallery
Click here for World Cup news wire

Nathan Astle led the way with a century as New Zealand produced a professional performance to keep their World Cup hopes alive on Saturday.

Needing to beat Zimbabwe in Bloemfontein to maintain any realistic hopes of reaching the semi-finals, the Kiwis looked in little trouble as they wrapped up a commanding six-wicket victory.

Astle's unflustered 102 not out saw them home after a 121-run stand with Chris Cairns had all but put the result beyond doubt.

It lifts the Kiwis into the top four of the Super Six with games against Australia and India still to come. Bottom side Zimbabwe's hopes now look a long shot with Kenya and Sri Lanka to play.

Although Chris Harris clubbed three fours to hasten the win with a late cameo of 14 not out, the game was effectively controlled by Astle's untroubled 122-ball knock.

Astle hit 11 fours but was well supported by Cairns, who weighed in with 54 after captain Stephen Fleming had got the innings off to a fine start with a fluent 46.

Zimbabwe, without leg-spinner Brian Murphy who tore a calf muscle practising between innings, enjoyed only limited success after Doug Hondo claimed the early wicket of Craig McMillan.

Fleming looked in fine form - but his dismissal lbw to Andy Blignaut, followed soon afterwards by the all-rounder's removal of Scott Styris, offered hope.

Yet other than Sean Ervine bowling Cairns the ball after he had moved to his half-century with a six, chances for Zimbabwe to make further inroads were few and far between.

Their disciplined bowling and fielding prevented the Kiwis from running away with victory - but with wickets in hand, their run-a-ball target was never likely to cause too many problems in the final 10 overs.

That Zimbabwe had set a testing total at all was due almost entirely to the gritty batting of Tatenda Taibu and captain Heath Streak. The pair came together with their side struggling on 106 for six but shared in a painstaking 68-run partnership to lay the platform for a late flurry.

Taibu hit a dogged 53 before being trapped lbw by Chris Harris attempting to flip the ball over wicketkeeper Brendon McCullum's head.

Streak, however, picked up the attack and went to his half-century with two sixes in a Harris over which went for 23. He finished 72 not out.

Ervine also joined in the late fun, cracking an unbeaten 31 from just 14 deliveries as 62 came from the final three overs.

The Kiwis had earlier wrested back control after a second-wicket partnership of 54 between Craig Wishart and Andy Flower had got Zimbabwe off to a solid start.

Cairns sparked a mini-collapse with the first of three Zimbabwe wickets for six runs which saw Wishart depart after a well- -constructed 30 and Grant Flower and Guy Whittall follow in quick succession.

Andy Flower looked to repair the damage but took on Astle's arm and became the first of two run-out victims after a promising 37. Andy Blignaut also went run out following a similarly sharp piece of work by McCullum.