The Bathurst-based club had to overcome a resilient Mudgee Dragons outfit in hot conditions at Jack Arrow Oval on Sunday, ultimately winning its Western Women's Rugby League semi-final 34-18.

It leaves the two-reigning premiers on the brink of claiming an unprecedented third consecutive title, with Orange Vipers standing in their way, having defeated Goannas 42-22 in the other semi-final.

Kathryn Gullifer, who touched down for a try in the first half for the hosts, said it was an awesome feeling to book a spot in the opens decider.

"We've just got to put our heads down and have a good crack next week.

"Those Mudgee girls were solid. Some of us play them in union, so it was a good match."

Speedy fullback Tiana Anderson had two tries within the first six minutes, but Mudgee hit back through Alyssa Shoulders to trail 8-6.

Gullifer, Cheynoah Amone and Menzi White all crashed over before the break, while Mudgee's Emma Cornwell got one for the visitors, as Platypi took a 24-12 lead to the half-time break.

Meredith Jones and Xanthe Booth would both score for the hosts in the second half, while Danielle Plummer scored a late consolation try for the visitors.

It was a hard fought win for Platypi, considering the comfortable 46-6 result against Mudgee last month, where the Bathurst club had a number of players unavailable.

But Sunday was the Platypi's first game in over a fortnight, due to a forfeit from Lachlan, followed by a bye.

"Having that forfeit didn't dampen things but it was hard to get a role on, because it is a short season," Gullifer said.

"But coming out here today and having a solid hit will make for a really good grand final."

The game was played in hot conditions, in stark contrast to the forecast for Saturday's grand final, which is expected to bring rain and much cooler temperatures.

Gullifer said it was a tough battle out there on Sunday with the heat.

"It was horrible," she said.

"Getting up off the ground after contact and then with the heat, it just gave that extra bit of sting.

"Two grand finals we played it in the rain, so hopefully we can do it all again if it rains."

All five grades - under 12s, 14s, 16s, 18s and opens - will be played at Jack Arrow Oval on Saturday, November 25.

Times are to be confirmed.

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