Milika Tiunakauvadra and Zali Waihape Andrews scored for Tuggeranong but it was the boot of Niki Paterson that proved the difference, nailing one of her conversion's to the visitors' nil.

The Brumbies representative did it all on her own, scoring both tries in spectacular fashion and breaking multiple tackles on her way to the line.

Royals coach Darren Goodwin was particularly impressed with his star players performance, heaping praise on the Test hopeful after the game.

"Grace stood up today and she played really well, she has developed great," Goodwin said.

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"She's only 19 so she hasn't got a great deal of experience but she's just a really great rough and tumble, hard running girl and she will only get better with more age and maturity."

Kemp's individual brilliance was the turning point for the Royals who had otherwise struggled to hold onto the ball in good field position.

"I've seen both teams play better flowing games but today was just a dog fight all the way through," Goodwin said.

"We want back to back premierships. It's the aim we have come back with this year and if we get our whole side on the field we are up there with Vikings and Uni-Norths to take it."

Uni-Norths battered Goulburn 33-3 in the other women's clash.

Meanwhile, the Queanbeyan Whites pulled off an upset 42-24 win over Wests to open their account in the fourth round of the John I Dent Cup at Jamison Oval.

Uni-Norths held off Gungahlin for a 32-21 win, while Tuggeranong's 32-22 triumph has left reigning premiers Royals to continue searching for their first victory.