The TAB was forced to abandon betting and refund money to punters after a worker failed to close betting lines on a $65,000 novice horse race.
At least 25 people had noticed the glitch during the Singapore race 5, novice 1200m at 1.20am (NZ time) yesterday morning and had placed a high number of winning bets on New Zealand-bred galloper Blue Swede.
A Hastings-based punter, who did not want to be named, said he'd placed a bet on the winning horse because dividends had started rising before the race.
"I noticed after the race they normally say dividends were now paying on such and such and that never happened," he said.
"I thought it was crazy, I've never seen this happen before. Overall it was quite strange."