David Johnson sparked wild celebrations from his coach after shooting Tasmania to within reach of an NBL finals play-in spot.
The JackJumpers' import guard scored 33 points and hitting the game-winning triple in a two-point defeat of New Zealand.
Sunday's 91-89 victory in Hobart shot the JackJumpers (13-17) to sixth, two wins clear of the seventh-placed Breakers (11-18).
Now sitting snug in the final play-in spot, Scott Roth's men need just one win from their final three games to cement a post-season berth.
New Zealand, who have four regular-season games remaining, as well as the Ignite Cup final, didn't lead until Parker Jackson-Cartwright (14 points, seven rebounds, five assists) got to the rim with 90 seconds to play.
The lead changed twice more, before Roth called a time-out and Johnson was given enough space to drain the match-winner.
Jackson-Cartwright had the ball inside the final 10 seconds before settling for a tough three-pointer that bounced off the front of the rim.
The triumph sparked wild scenes, led by the elated coach who lapped the court theatrically celebrating with the crowd.
"Our motto is to defend the island," Roth said, having battled a tough early-season schedule and consistent injuries.
"I'm obviously quite passionate about Tasmania and the statement by the players to continually show up.
"It's a credit to the guys we get here; the unselfishness, the warrior mentality.
"The grit and grind is real and if we had lost this game, I would have been just as emotional with them."
Johnson made seven-of-11 triples as the JackJumpers found their best offensive form of the season and brushed off a shock loss to Cairns earlier in the round.
Josh Bannan (16 points, 11 rebounds, five assists) was busy for the hosts while Majok Deng had 17 points and two blocks.
Breakers import Izaiah Brockington (24 points, seven rebounds) led the scoring for the visitors, who surged from as far back as 12 points to ensure a nervy finish.
"It's part of their DNA and how they do things here. It's never easy," Breakers coach Petteri Koponen said.
"This was a big game … (but) as long as there is some hope, we keep fighting.
"He (Johnson) was really good. We knew he had to take the responsibility with (Bryce) Hamilton out and we couldn't stop him."
