McCullum, who opened the bowling for Black Caps, bowled a tight line, giving little away, despite Zimbabwe getting off to a sound start.
However it was in his second spell that McCullum wreaked Zimbabwe completely, taking three wickets in one over, from which the minnows could never really recover.
He first picked up Elton Chigumbura, who tried to hit his way out of the pressure situation, only to spoon it to Martin Guptill [ Images ] for three runs.
Two balls later he sent Charles Coventry back to the pavilion, when the left-hander lobbed an easy catch back to the bowler. He then enticed Craig Ervine to chip down the track, but he misread the flight of the ball, and was easily stumped by Gareth Hopkins for just one.
Zimbabwe were reduced to 63 for six from a comfortable 59 for two. McCullum finished with figures of three for 16 in his four overs.
Later on Scott Styris [ Images ] too joined the party and picked up three wickets in an over as Zimbabwe were bundled for just 84.
Chasing 85 for a win, New Zealand made 36 for one from 8.1 overs before rain interrupted play with Brendon McCullum [ Images ] and Martin Guptill at the crease on 22 and six respectively.
At that time, New Zealand were seven runs ahead of par score under D/L method.
Rain stopped after around one hour but confusion prevailed as the target was revised twice as players were out to resume play only to end it abruptly.
After the first revision, the target for New Zealand was 45 from 11 overs but had to be changed to 40 from 10 overs. But all of a sudden, the match ended apparently because the ground was not ready for resumption of play after the heavy rain.