Nelson remained in the lead thanks to a hot start from three point range, with guard Jarrod West (3/5 in the first quarter) particularly accurate from well behind the arc.
The Hawks eventually took the lead at the seven minute mark, and held on for a 24-22 lead at the end of the first period.
Nelson responded with some aggressive offence of their own after the break, drawing five team fouls on the Hawks inside five minutes of play.
They also enjoyed an offensive rebounding advantage (9-2 in the first half) which helped fuel a six point lead at the four minute mark of the second quarter.
It was the Hawks turn to catch fire from deep – they hit five three pointers over the rest of the half to flip that deficit into a 49-43 lead at the break.
Hawke's Bay carried that momentum into the third quarter as well, finding offensive success by pushing the ball in transition and attacking mismatches in a scrambling Nelson defence.
They built a 10 point lead over the first few minutes of the second half, but the Giants crawled back into the contest through solid defence and drawing fouls on the other end.
By three quarter time, Nelson had shot 17 free throws for the game compared to just five for Hawke's Bay.
The Hawks only managed 13 total points in a mucky third quarter that ended with the score at 62-62.
Defensive rebounding continued to be a problem for the Hawks into the fourth period with the Giants increasing their advantage on the offensive boards to 21-8 by the end of the game.
It was another sluggish quarter from Hawke's Bay with the ball as well, with Nelson's active, stingy defence keeping them to 14 points in the final term.
Another long three pointer from Jarrod West extended the Giants' lead to nine with a little over two minutes left and they never looked back.
The Hawks' next game is against the Manawatu Jets in Palmerston North on Tuesday night, before they return home for the Otago Nuggets' visit on July 11.