Phillips hit 104 from 64 balls before Trent Boult claimed 4 for 13 to secure a comfortable victory over the Asia Cup winners at the Sydney Cricket Ground
Sydney: New Zealand 167-7, Sri Lanka 102 - New Zealand won by 65 runs
New Zealand strengthened their position in the Super 12s after surviving a scare to beat Sri Lanka in Sydney.
Glenn Phillips hammered 104 off 64 balls, his second in T20I cricket, as the Kiwis recovered from 15 for 3 to make 167 for 7.
Kasun Rajitha took 2 for 23 and there were wickets for Dhananjaya de Silva and Wanindu Hasaranga but the Asia Cup winners were unable to sustain their early success.
Dasun Shanaka's side never got going in the chase, being reduced to 8 for 4 midway through the fourth over.
Trent Boult produced his best T20I figures of 4 for 13 as Sri Lanka were bowled out for 102 in 19.2 overs.
The 65-run margin of victory was the biggest by the Black Caps over Sri Lanka in T20Is.
Trent Boult finished with career-best figures at the SCG (DAVID GRAY/AFP via Getty Images)
Bhanuka Rajapaksa (34) and Shanaka (35) provided some resistance and a brief glimmer of hope but they were the only two batters to bring up double figures.
The result means the Black Caps have a two-point cushion at the top of Group One ahead of facing Ireland (October 31) and England (November 1) at The Gabba. Victory in either will very likely be enough for a semi-final berth.
Sri Lanka, meanwhile, remain fifth with two points from three games and face an uphill task to qualify for the last four.
Indeed, the target for Chris Silverwood's side will be ensuring they finish in the top four and earn direct passage to the 2024 T20 World Cup in United States and West Indies.
They face bottom-side Afghanistan (November 1) before rounding off their campaign against England (November 5) next weekend.
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