Brendon Howe hit a three-pointer for the Aucklanders, while Jacob Tapiata was able to get up for some tip-ins off the rebound for OBC.
OBC's Logan Funnel seemed to loosen the shackles when he hit a three-pointer for a 21-17 advantage, but Horzlyf worked back into territory and had the lead until Jade Brown caught fire for the locals.
The No15 nailed a hat-trick of three-pointers either side of the buzzer for the fourth quarter as OBC extended briefly to 35-28.
Horzlyf closed the gap back to two points with just over a minute left and then OBC's veteran Stacey Lambert showed all his guile.
Taking control of the situation, Lambert slowed the action down outside the Aucklander's circle and at the end of a shot clock hit a three-pointer.
Lambert then drew a foul with only seconds left and converted both to lead his team through.
In the Women's Premier final, a separate game for the two premier teams who had combined with Women's A for the weekend, Waitakere Super City Lady Rangers beat Hawera Southern Storm 47-20.