After trailing for most of the game, Camaira muscled her way over as the siren sounded to give Western a stunning 22-16 win over the Monaro Colts at Les Boyd Oval in Cootamundra.

"It was a good second half performance from our girls," Rams coach Kaitlyn Mason said.

"Coming off at halftime we knew we needed to improve and we spoke about that. We knew if they had too much time with the ball then they were going have us on the back foot.

"The girls made those changes. We made some silly mistakes in the first half and we cleaned that up to put in a good performance."

Earlier in the match, Western had several chances to score early but couldn't find a way before Monaro produced a moment of brilliance of a scrum.

Monaro backrower Uta Uatisone Poka beat several defenders and found herself in open space to score under the posts.

Following a successful conversion, the Rams found themselves trailing 6-0 but couldn't hold onto the ball in good field position.

A try to Monaro's Adelaide Norris just before halftime gave the Colts a 10-0 lead heading into the break.

Things couldn't have started better for Western in the second half with Monaro making an error off the restart before Adda Craig scored just a minute later.

Starting off the bench, Craig was one of several players who made an immediate impact Mason thought.

"Those changes worked and the girls came on when we needed them to," she said.

"They got us going forward and when they had the ball they ran with a lot of heart. The bench was tremendous for us today and really made the difference.

"They lifted the girls when they went on too which was really helpful, they played for each other today."

Following Lara Edwards' successful conversion, the Rams were back in the game, trailing 10-6.

Western co-captain Alana O'Loughlin barged over several defenders to lock tie the match just eight minutes into the second half.

Edwards made no mistake with the kick once again, giving the Rams their first lead of the afternoon.

With less than 10 minutes in the match remaining, the Colts scored again, this time through Teuila Ahkey.

Monaro led 16-12 with seven minutes left in the game but Western would have another chance to score courtesy of a clever one-on-one strip.

Grace MacGregor backed up a 20m run with a try on the next tackle, a four-pointer which locked the scores up at 16-all.

Lara Edwards couldn't score her third conversion of the afternoon but as the clock winded down, Western made a break off the kick-off thanks to Zakiah Jenkins.

As the siren blew, Western turned Camaira back under as the damaging prop scored next to the posts to seal the win.

Western will now take on Northern Tigers at Woy Woy on March 23 in the competition's final.