The Waratahs women are in the box seat to host the Super W final for the second year in a row after a 15-12 win over Queensland.
With two rounds to go, NSW and Queensland both have two wins but the Waratahs have a game in hand on their northern rivals.
Queensland faces the Brumbies at home next weekend before a final round bye, while NSW takes on RugbyWA in Perth before hosting the Rebels in a fortnight.
The side that finishes on top of the ladder will host the Super W final while the second and third-placed sides clash in a newly-introduced playoff match.
Queensland struck first in the sixth minute, converting some early pressure through winger Alana Elisaia.
The Waratahs had the chance to hit back with a penalty in the 12th minute but Ash Hewson’s shot missed.
NSW pulled out something spectacular for their first try in the 15th minute, finished of by Maya Stewart.
Fullback Hewson managed to stay just out of touch on the right sideline and the Waratahs went edge to edge to put Stewart through a gap and the winger powered over.
Shanice Parker had her hand in that first and the left winger found her own score in fortuitous circumstance not long after.
Queensland fullback Lori Cramer fell just short in her chase a kick receipt deep in NSW attack and the ball bounced into her face before rebounding into open space for Parker to run onto.
The Queenslanders were left a player down when Christina Sekona was sent to the bin in the 32nd minute and the Waratahs began to build momentum after that.
Queensland looked on their way to a second try just before the break as Ivania Wong found space but Parker again made her involvement felt, pushing her opposite number into touch.
The second half was more of an arm wrestle than the first with neither side able to add to their tally more than 25 minutes into the stanza.
Queensland broke the second half duck in the 68th minute through Wong, narrowing the margin to three points, and their confidence clearly grew from there.
The Waratahs defence held Queensland out at another opportunity late in the piece but it was the hosts who were under all the pressure.
A timely penalty gave the Waratahs a chance to gain some territory and turn the pressure valve off but Queensland weren't done yet.
Waratahs halfback Iliseva Batibasaga won a foot race to ground a loose ball in-goal in the final minute to deny Queensland a last-gasp try and the visitors ultimately ran out of time.
RESULT
Waratahs 15
Tries: Stewart, Parker
Cons: Hewson
Pens: Hewson
QLD 12
Tries: Elisaia, Wong
Cons: Cramer
Yellow cards: Sekona (30’)