Rangers coach Jeff Green, who has denied any wrongdoing by his team, said the final timeout was called to give a departing player the final shot.
A number of sources told the Herald that multiple Rangers players appeared to be furious when the Airs reduced the deficit to nine points with two seconds remaining.
The NBL has commissioned the TAB to look into those circumstances, and the Rangers' participation in the 2019 NBL is also under review.
NBL chairman and Basketball New Zealand chief executive Iain Potter confirmed that while seven of the NBL's eight teams are likely to return for next season, the Rangers' status is in doubt.
"Seven of [the teams] have expressed to me in recent weeks that they absolutely want to be there, but the Rangers have struggled this year and we are talking to them regularly about what next year might look like. As of right now they are the only ones who are expressing that they just need a little bit of time to work through whether they can make a commitment to next year."
It has been a difficult season for the Rangers, who finished in sixth place with just four wins and 14 losses. The franchise had made the playoffs for the last three seasons but had fewer resources in 2018, meaning they struggled to lure local talent.
Additionally, their imports were a decidedly mixed bag, with one of them – Junior Ale – being a bizarre signing, averaging just 6.7 points per game on 41 per cent shooting.
That, plus a lack of promotion by the franchise, led to non-existent home crowds throughout the campaign, something Potter has noted.
"There's really strong live audience numbers at seven of the teams, the only exception being the Rangers, which has been a struggle this year, it was a struggle last year as well."
If the Rangers were to fold, it would leave the NBL with just seven teams, with Potter confirming that Tauranga – who bid for a spot in the league last season – have not expressed interest for the 2019 season, while other suitors are still several years away from returning.
"Otago remain warm to the idea that they will come to us at some stage but not for 2019, they are still taking a conservative approach to coming back to the league. We encourage them to keep interested but make sure they are really ready when they do come back. At this stage, that's about it."
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