"I put a really good swing on the 10th hole and came within a foot, which kept the momentum going.
"It's my lowest round. You don't have many arguments after [shooting] 61.
"That one of the things about golf it's not the sanest game."
The anguish came from defending champion Michael Hendry who threw his putter after the final hole at Millbrook. He finished at four-under par overall, missing the cut by three strokes.
The club came close to making contact with New Zealand great Michael Campbell during a television interview with Sky Television's James McOnie.
"I'm pretty gutted," Hendry told the Herald. "I was taking my frustration out on the putter and was attempting to throw it into the pond when it hit some rocks.
"I appreciate it wasn't the most mature or professional reaction, but I feel like I've been playing poorly of late. It was a lapse in judgment, I was trying to win the national open again and it's been a tough period."
"I hope people appreciate the pressure we're under, and the expectations we put on ourselves, but it doesn't excuse letting go of the putter. I'm only human, and I'm going through a rough patch on and off the course."
New Zealand No.1 Ryan Fox also missed the cut, by one stroke. He bogeyed the last.
Harry Bateman remained the best of the Kiwis, shooting five-under par at The Hills to match his seven-under par at Millbrook. That left him three shots shy of the lead.
Tim Wilkinson was a shot further back.
"The front nine [holes 10-18 at The Hills] was pretty good - I made some nice putts and scored 29," Wilkinson said.
"The back nine [holes one to nine] I left a few out there. I made a good putt on six for birdie, hit a few that slid by and made a soft bogey on the ninth."
Wilkinson said he played the par-5s well.
"Mixed with three birdies and a couple of eagles, that makes it easier. Hopefully I can get to 22 or 23-under which would be a good score.
"If the weather stays like this it is calm and very score-able. Obviously the pin locations will be trickier with fewer amateurs playing [in the final rounds]."
The field played in cool, overcast conditions in the morning, before the sun burst through.
The lack of wind meant Pilkadaris was unable to draw on the experience of yachtsman Sir Russell Coutts, who was part of the playing group in the pro-am format.
"I was going to ask him a couple of things, but there was no breeze to factor in today."
More rain and a gentle south-westerly breeze are forecast for the afternoon of the third round.
