"I thought if we could go at eight or 10 an over and try to take it as deep as we can, we would always have a chance to go over the line. It was about taking it ball by ball and not thinking too much about the end result."
Ervine, en route to the highest score by a Zimbabwean in a successful ODI chase against a test nation, had mustered six half centuries from his previous 32 ODIs. Today he rattled up five sixes and 11 fours to carry his country home.
Zimbabwe had won only one, and lost 10 out of 13 ODIs this year, and lost 15 of their last 17 ODIs in Harare. New Zealand had won nine of their last 10 clashes.
So an early banana skin for New Zealand as their undermanned squad begin their African trip.
Earlier there was a third ODI ton in his last five innings for Ross Taylor, an unbeaten 112, and 97 from captain Kane Williamson - the pair putting on their 10th 100-plus stand, 137, in ODIs.
Taylor is now up to 15 centuries, one behind New Zealand recordholder Nathan Astle and both Taylor and Astle continued a stellar run of form in the 50-over game.
Indeed it was Taylor's 27th century in all forms for New Zealand, also one behind Astle's record.
However it counted for nothing as New Zealand's bowlers slipped up.
None of the main five used cost less than five an over.
Offspinner Nathan McCullum was the most expensive in runs per over terms, costing 62 off his nine, but picked up two of the wickets; while Matt Henry, Jimmy Neesham, on his international return from a lengthy injury layoff, and legspinner Ish Sodhi, on his ODI debut, all copped serious treatment.
"Zimbabwe always play well at home but we'll analyse it and come back better in a couple of days," Taylor said.
"You've still got to give a lot of credit to Zimbabwe. They executed their plans a lot better than us and were too good on the day."
Taylor felt New Zealand's 300 total was a touch better than par on a slowish wicket ''but we weren't able to pick up wickets.
"Ervine and Masakadza batted outstandingly and took the game away from us. To get there with an over to spare was a very good effort."
The second of the three ODIs is at the same venue starting on Tuesday night.