The Giants have broken their Super Netball duck with a controversial and chaotic 86-80 overtime win over Sunshine Coast at Ken Rosewall Arena, after the Lightning had initially been declared victors amid a bizarre score bench bungle.

The Lightning, believing they were protecting a one-goal lead, played keepings-off in the last half-minute of regulation on Saturday night, before the fulltime siren sounded with the stadium scoreboard showing them ahead 71-70.

Players and coaches from both sides shook hands, Lightning shooter Cara Koenen was announced player of the match and disappointed fans began filing out the exit doors.

But there was a discrepancy with the final scores, with Champion Data declaring a 71-all draw.

The umpires and Lightning players had already headed to their rooms but the Giants stayed on the court, expecting extra time.

They were adamant there had been a technical error and that the scores were tied.

"We were always very confident that it was a draw and we actually protested at the time that the score was changed," Giants coach Julie Fitzgerald said during the protracted 50-minute delay between the end of regulation and the start of overtime.

"The players were aware it was a draw.

"When we came off, we were a little bit bewildered.

"I would have thought that there would be some sort of provision in place for what should happen now."

The stats bench furiously went back through the match feed and examined each fourth-quarter goal.

Twenty minutes after the fulltime bell, the stadium scoreboard was officially updated to 71-71.

There was a competition rule change before the season that drawn games would require overtime, but an exception looked an option when it was thought the umpires had left the building.

The umpires eventually emerged and were re-microphoned, while the Lightning players also re-entered the arena.

"(We were told) that there was a score review and a drawn game," Sunshine Coast coach Belinda Reynolds said shortly before play resumed.

"We're a little disappointed at that because obviously we had possession in the last part of the game, which we would have played a lot differently and gone to post."

Fitzgerald pulled off a shock coaching masterstroke to begin overtime, replacing captain Jo Harten with unused sub Matisse Letherbarrow.

The sharpshooting replacement duly nailed nine goals, including three super shots, as the Giants snatched the match away from Sunshine Coast with a 11-1 blast to start the extension.

It was heartbreak for the Lightning for the second week in a row, after the Melbourne Mavericks pinched a miracle win from them last week.

Prior to the controversy, the match had been a high-class thriller, with no more than one goal separating the two sides at any break.

Koenen nailed her first 33 shots while Lightning teammate and Diamonds skipper Liz Watson racked up a whopping 36 assists and 66 feeds.

At the other end, Sophie Dwyer was a shooting force, Jamie-Lee Price consistent in the middle and Letherbarrow the hero at the finish.

AAP