Vaas took all four wickets, and was sitting on a hattrick when Fleming came to the wicket to join Vincent and swing the Test back in New Zealand's favour with an unbroken 100-run partnership.

Playing in his 20th Test, Vincent reached the milestone of 1,000 Test runs as he posted his ninth half-century in reaching 79 when the rain set in.

He had faced 188 balls and his innings included eight fours and a magnificent six driven straight back over the head of Mahela Jayawardene.

Fleming was not out 60, also with eight boundaries, finding timely form after a disappointing season and showing little effect from the knee injury that kept him off the field for much of the first day of this Test.

The pair came together after Vaas trapped opener Craig Cumming leg before wicket for 47 and followed up the next ball with the prize wicket of Nathan Astle who appeared to glove the ball to Tillakaratne Dishan as New Zealand fell from 153 for two 153 for four.

It was a welcome return to form for Vaas who failed to fire on the flat wicket in Napier in the drawn first Test.

On the slightly livelier conditions in Wellington he has been Sri Lanka's most effective bowling weapon, taking two wickets on the first day and starting the second by trapping James Marshall leg before wicket for 28 in his third over.

New Zealand's in-form batsman Hamish Marshall faced just six balls before he drove at a Vaas off-cutter and edged it to Jayawardene at first slip to be out for six.

Vaas posed a constant problem and finished the day with four for 69 off 24 overs, while Farveez Maharoof could consider himself unlucky not to capture Cumming's wicket when Kumar Sangakkara dropped an inside edge.

But young speedster Lasith Malinga, who took a man of the match nine-wicket haul in Napier, failed to threaten and has figures of nought for 56 off 15.

Sri Lankan captain Marvan Atapattu was reduced to using Malinga in short bursts to try to keep the brakes on New Zealand, and operated with a seamer and a spinner bowling in tandem.

Upul Chandana proved particularly effective without reward, giving up a miserly 21 runs off 13 overs.

But while New Zealand appear to have the upper hand after two days, the weather could count against them.

A few weeks after they prayed for rain to save them in the second Test here against Australia, they now have unwanted rain forecast for the third day of the Sri Lanka Test.