Stuck in catch-up mode from the first centre pass, the Ferns struggled to get the upper hand over a polished Diamonds side. Star shooters Maria Folau and Ameliaranne Ekenasio had their work cut out for them in the circle, with the Australians displaying tighter defence on the pair.
Ekenasio, in particular, struggled to free herself from Jo Weston and Courtney Bruce, leaving Folau to take the bulk of the shots - something head coach Noeline Taurua agreed had let them down.
"It was really physical out there and I thought in our attacking end we got caught running side to side and probably didn't get enough penetration onto the circle edge, not as much as we did on the first test," Taurua said after the game.
"I thought equally in our circle as well, we got caught behind the person and they were pretty tight defensively.
"Look, we put our hand up, we lost and there were some areas they were way better in than us but I know that there are some areas we were actually quite good in. We've just got to be smarter, cut down some of those errors as well as we're going through the court."
Ferns defender Karin Burger carried her fine form from Sunday's clash, snatching five intercepts during the game, and backed up by the aerial skillset of Jane Watson, the defensive duo gifted their side possession at crucial moments – but it was in the shooting end the ball was continually lost.
Ekenasio found better space in the circle in the second half, but captain Laura Langman struggled to find consistent openings to feed to her shooters from the circle edge.
Taurua's first change came in the third quarter with Whitney Souness given the nod at wing attack while Shannon Saunders took a seat on the bench.
Souness' influence was instantly felt on court. The young midcourter picked up plenty of ball while finding good connection with Folau.
As Ekenasio continued to struggle under the post, Bailey Mes came on at goal shoot, allowing Folau to move out at goal attack.
The switch momentarily caught the Australian defenders off-guard but it didn't take long before the Diamonds regained control to confidently claim the second test of the series.
Hope of bringing home the Constellation Cup for the first time in seven years isn't lost yet for the Ferns though, as two games remain - though both are to be played on Australian soil.
The sides have four days of travel, rest and training before they face off again in Sydney on Sunday.
The final test will be hosted in Perth on October 27.
