Fullback Mahalia Murphy has produced some magic, bagging five tries as the Waratahs romped to a 60-10 Super W win over Melbourne at the SCG on Saturday.

A five-try haul by Mahalia Murphy has highlighted the NSW Waratahs' crushing 67-10 victory over Melbourne Rebels at the SCG to continue their unbeaten Super W streak.

The powerhouse Tahs, who haven't lost since 2018, have now stretched their winning run to 21 games.

Fullback Murphy was unstoppable early, crossing three times by the 30 minute mark to help set up a 22-5 halftime lead before the NSW outfit added a further seven tries in the second stanza for a tally of 11.

The 28-year-old, who has represented Australia in both league and union, had too much power and pace for the Rebels.

She was ably assisted by Katrina Barker, with the inside centre setting up her second try with a long ball before Murphy cut back inside to score.

Winger Lori Cramer also finished with a double.

NSW skipper Grace Hamilton said Murphy was a great finisher.

"She's little, she can finish and that's what we need from her so I'm really stoked for her," Hamilton told Stan Sport.

"For us it about building phases - we wanted to build a platform because when we do we know we can score points."

The Rebels' points came from a try in each half scored by hard-working prop Janita Kareta, with the courageous visitors simply outclassed.

Their captain Mel Kawa praised their resilience.

"It was always going to be a massive ask against the Tahs and they managed to stick to their game plan a lot more than we did," the flanker said.

"We were valiant ... a lot of learnings to take away."

While Murphy was the hero for the Waratahs, she had to share the tryscoring spotlight with Eva Karpani.

The reserve prop made a bullocking 60-metre charge to the line before being swamped by her joyous teammates.

Murphy's magic continued until the final whistle, grabbing for her fifth try in the 83rd minute to cap a memorable afternoon for the home side.