Silver Ferns defender Anna Harrison is preparing to unleash a bold new defensive tactic in tomorrow's Constellation Cup finale in Invercargill.

The athletic defender, who introduced the Harrison Hoist - a ploy where a defender is lifted in order to block a shot - to top level netball, has been working on a new innovation on her defence of the shot.

The Ferns have trialled the new move in training this week as they continue to look at ways to curtail the impact of 1.93m Diamonds shooter Caitlin Bassett.

New Zealand coach Janine Southby said she is comfortable with Harrison using the tactic in the final clash of the series tomorrow after the umpires found no issue with the move when it was used in this morning's training match.


"I think the girls are keen to have a go, we were just seeing what reaction we got today [from the umpires] and they were okay with it," said Southby.

"The big thing is the timing of it. The game is so fast so it is not going to happen every time, but I certainly think it's something we can use going forward."

Harrison warned the defensive ploy is still being perfected and it won't be the magic bullet to breaking down the well-drilled Diamonds attacking unit.

"It's very new, and there will be bloopers. We might not even get to do it. It's kind of similar to the lift in that you can only do it when everything aligns," the veteran defender said.

"I don't know if it is going to be as effective I had hoped in my mind, but I definitely want to put it out there and it's all about getting the shooters to think about something else other than being comfortable under the goal."