"The front nine was awesome today in that wind. I just felt like, I don't know, I couldn't do anything wrong," Cusdin said.
"Then on the greens I was putting shots, too, that went along with it, which was giving me confidence. On that front nine this morning if you missed any shots the wind just caught it."
Despite winning the Tauranga Open, a Charles Tour event, he admitted it was nice to come in to this week with no expectations on him.
"There's obviously a lot of good players here ... You've got guys like Craig Parry and that who have won in the US. In saying that, it is, I suppose, a weaker field than normal. But yeah. It's kind of good flying under the radar."
Cusdin, who plays out of the Hamilton Golf Club, looked particularly strong off the tee during his round.
After a blistering front-nine, which featured six birdies and one bogey, it looked like it may turn pear-shaped when he double-bogeyed the 13th and dropped another on the 14th.
But, he kept his composure and finished with two birdies and a couple of pars.
"I said to my caddy Scotty my goal for this week, whatever happens, [is] just stay cool and that's golf.
"It was a tough day today. It was just grinding all day ... I'm happy with the end result on a day like this today. It's pretty unlikely you'll get around without having a bad shot or slightly missing one."
Cusdin is hoping to base himself out of Melbourne next year and play on the PGA Tour of Australasia; if he keeps up his form this week, that won't be a problem.
In what was a challenging opening day, the players in the morning got the better of the conditions, with the wind less of a concern.
Only 13 players in the 144-strong field went under par on a round, which also featured a hole in one by Australian Jason Scrivener on the fourth.
Former champion Mahal Pearce carded a useful two-under 70, while fellow Kiwis Steve Alker, Josh Geary and Jordan Dasler were all one under.
Fan favourite and 2005 US Open champion Michael Campbell opened the day well and found himself at two under before he trailed off and finished the day at a disappointing five over.
Kiwi Phil Tataurangi also flirted with shooting a great round and was at three-under the card before he closed the day at one over.
Veteran Australian Parry is lurking in the field at two under, alongside Pearce and Nicholas Cullen.
Those who played in the afternoon get the chance to experience the morning conditions today when the playing order reverses.
The wind has been unpredictable during the past few days but is at its strongest in the middle of the day so playing early doors is an advantage to beat the stiff breeze.
Scores after round 1 (a- denotes amateur):
68: Brad Kennedy (AUS), Jim Cusdin (NZL).
69: Leigh McKechnie (AUS), Doug Holloway (NZL).
70: Craig Parry (AUS), Mahal Pearce (NZL), Nicholas Cullen (AUS).
71: Andrew Evans (AUS), Steve Alker (NZL), Josh Geary (NZL), Jordan Dasler (NZL), Steve Horstmann (AUS), Paul Spargo (AUS).
72: Craig Hasthorpe (AUS), Luke Bleumink (AUS), Ryan Haller (AUS), Peter O'Malley (AUS), Ryan Fox (am, NZL), Mitchell Brown (AUS), Jake Higginbottom (am, AUS), Rohan Blizard (AUS), Josh Younger (AUS), Henry Epstein (AUS), Leigh Deagan (AUS), Carl Brooking (NZL), Tim Leonard (am, NZL).
73: Dean Meagher (AUS), Rhein Gibson (AUS), Ashley Hall (AUS), Marcus Cain (AUS), James Carr (AUS), Phil Tataurangi (NZL), Simon Furneaux (AUS), Daniel Pearce (am, NZL), Blair Riordan (am, NZL), Jin Jeong (AUS), Andrew Martin (AUS), Tristan Lambert (AUS), Steve Jones (AUS), Rhys McGovern (AUS).
74: Joon-woo Choi (KOR), Peter Shaw (AUS), Andrew Kelly (AUS), Aaron Cox (AUS), Peter Wilson (AUS), Terry Pilkadaris (AUS), Adam Crawford (AUS), Terry Price (AUS), Thomas Spearman-Burn (am, NZL), Michael Wright (AUS), Brent McCullough (AUS), Ben Wharton (AUS).
75: Daniel Fox (AUS), Anthony Doyle (NZL), Kieran Pratt (AUS), Ben Campbell (am, NZL), Chad Inkster (AUS), Peter Lee (am, NZL), Michael Smith (am, NZL), Darren Tan (AUS), Ed Stedman (AUS), Leighton James (NZL), Nick Gillespie (NZL), Peter Spearman-Burn (NZL), Peter Cooke (AUS), Peter Nolan (AUS), Michael Hendry (NZL), Jonathan Ratcliffe (am, NZL), Andrew Tschudin (AUS), Michael Choi (AUS), Jason Scrivener (AUS).
76: Michael Foster (AUS), Michael Gannon (AUS), Anthony Brown (AUS), Adam Bland (AUS), Chris Hartas (AUS), Brett Rankin (AUS), Pieter Zwart (NZL), Nick MacKay (AUS), Chris Gaunt (AUS), Stephen Dartnall (AUS), David Klein (NZL), Marcus Wheelhouse (NZL).
77: Jonathan Park (am, NZL), Michael Campbell (NZL), David Smail (NZL), Max McCardle (AUS), Brenden Stuart (NZL), Jason Yoo (am, NZL), Jamie Arnold (AUS), Grant Moorhead (NZL), Ewan Porter (AUS), Josh Carmichael (NZL), Sam An (am, NZL), Cody Sherratt (AUS).
78: Vaughan McCall (am, NZL), James Byrne (SCO), Tony McNaughton (AUS), Jason Norris (AUS), Dominic Barson (NZL), Dean Sipson (NZL), Peter Welden (AUS), Damon Welsford (AUS), Heath Reed (AUS), Brad Shilton (NZL), Brad McIntosh (AUS), Neven Basic (AUS), Keelan Kilpatrick (am, NZL), Mathew Holten (NZL), Steve Jeffress (AUS), Kurt Carlson (AUS), Aaron Black (AUS), Nic Kay (am, NZL).
79: Corey Hale (AUS), Mark Purser (NZL), Luke Hickmott (AUS), Tim Wood (AUS), Hamish Robertson (NZL), Rowan Beste (AUS), Brad Lamb (AUS), Kevin Conlong (AUS).
80: Kieran Muir (NZL), Michael Etherington (AUS), Michael Craig (AUS), Chris Renouf (AUS), Paul Donahoo (AUS).
81: Brendan Smith (AUS), Deyen Lawson (AUS), Kalem Richardson (AUS), Brett Drewitt (am, AUS), Mathew Perry (am, NZL), Grant Scott (AUS), Scott Arnold (AUS), Michael Moore (AUS), James Smith (am, NZL).
82: Jared Pender (NZL), Owen Burgess (am, NZL).
83: Brad Kendall (am, NZL), David McKendrick (AUS), Martin Dive (AUS).
84: Craig Palmer (NZL), Josh Munn (am, NZL), Adam Stephens (AUS).
86: Ryukoh Kanazawa (am, JPN).