"He thought, well, it's got to be the cricket," his mother Jenny said. His father was born in Christchurch so in 2009 he packed up his kit and headed east. "He surprised himself, actually. He just went over there on a wing and a prayer."
Brownlie said he "wanted to give cricket a good go and I felt that my opportunity in WA was slipping and I would probably miss my chance".
Fast forward three years, having made a decent fist of his time with Canterbury, and having had a brief taste of international cricket in a couple of T20 internationals against Pakistan last season, Brownlie is making the most of a chance on the biggest stage the game offers.
He made 63 against Zimbabwe on debut last month and followed up with a composed and crucial contribution at the Gabba. He shared a New Zealand record 158 stand for the sixth wicket against the Aussies with Dan Vettori to pull his team out of a deep pit at 96 for five.
Brownlie also enjoys coach John Wright's confidence. Wright is known to like the cut of Brownlie's jib.
He is not a garrulous chatterer but, rather like his batting style, is clipped and unfussy.
"This time two years ago, I was playing club cricket," he said. "It's unbelievable how much has changed and I'm loving every minute. I've been given a great opportunity from New Zealand so it's an awesome honour to play for them."
Brownlie had serious wobbles in the early stage of his innings on Thursday, dropped twice in three balls on three. He looked jittery. But the calming influence of the old hand Vettori helped and, having got through to 32 that first day, Brownlie emerged a far more poised, organised batsman.
It was as if he realised that he did have a right to be in this company. He admitted he'd ridden his good fortune.
"Sometimes it happens for you, sometimes it doesn't. I could easily have chopped it on at some stage and next time I might not have that luck."
As a youngster Brownlie supported Australia, but confessed to a soft spot for the underdog. So..."after 10 years of Australia dominating you'd always hope to see them lose at some stage - for the good of cricket".
Brownlie, as a relative latecomer to international cricket - he's only playing his 18th first-class game, is averaging 56, and has gone past 50 10 times in 31 innings - isn't about to get ahead of himself.
"I don't know if I belong yet. I've only played two games for New Zealand. There's a long way to go before I cement a spot or prove myself at this level."
What can be safely assumed is that he's got a lock on the No6 spot for the immediate future. Grafting just over four hours against the Australian bowlers suggest he's got a bit about him.