Colin Munro was only too happy to play a supporting role to Kane Williamson and Martin Guptill in New Zealand's thrilling Twenty20 victory over Sri Lanka.

Williamson (53 off 42 balls) and Guptill (58 off 34) were in typically free-scoring mood at the Bay Oval on Thursday as the hosts won the opening T20 match by three runs after posting the tourists a target of 183 for victory.

Munro came to the crease in the 11th over when Guptill was run out and his quick-fire 36 off 26 deliveries alongside Williamson and was a major factor in New Zealand moving 1-0 up in the two-T20 series.

"It took a couple of balls to get the nerves down, and once I was away I felt pretty good," he said.

"It's a big area of my game I've worked on over that last six to 12 months; that I can catch up at the death if I'm still there. It was a hard surface to get start on and Sri Lanka bowled really well after the Guptill wicket.

"It was a tough period to go in, after the start that Guppy and Kano got - 'do I keep going or give myself a little bit of a chance to get in?'

"I spoke to Kane and he said give yourself a few balls to get in and once I got in I felt I could make hay."

Meanwhile, Sri Lanka's Chamara Kapugedera, the man who ran Guptill out, refused to be too downbeat after the defeat.

"A loss is always not satisfying, but I think we fought well," he said.

"We lost in the first 10 overs in each innings - they batted well in the first 10 overs and looked like getting to 200.

"When batting, we lost quite a few wickets and it's hard when you do that to come back."