Ruby Tui starred as New Zealand waltzed past Australia in the Las Vegas sevens final.

The New Zealand women's sevens side thrashed Australia 28-5 in the final of the Las Vegas tournament.

The Black Ferns scored two tries in each half, while the Olympic champions only managed a consolation try just before full-time.

The men's side have qualified for the semi-finals after a comprehensive 19-0 win over England.

Bradley Kanaris Portia Woodman scored a crucial try against Australia in the final in Las Vegas.

They will face old foes Fiji on Monday.

Veteran DJ Forbes scored the All Blacks first try, after a piece of quick thinking from 18-year-old Vilimoni Koroi.

Koroi took a quick tap and advanced on England's defenders before off loading to Forbes, who scored his 144th career try.

Up 7-0 at the break Tim Mikkelson got their second when he too took a quick tap close to the line.

Mikkelson then sealed the win with a long range effort, including a chip and chase, to seal the win.

For the women Ruby Tui was the star for New Zealand with an outstanding individual try and three big line breaks.

The win meant the Allan Bunting coached side extended their lead in the overall championship to six points.

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​The table remains tight with New Zealand on 56 points, Australia 50, while Canada have 46, after finishing the tournament in third place.

Tui opened the scoring with a strong run from her own half, then fooled the defence with a stop-start move to score.

Tyla Nathan-Wong converted as she did for all four New Zealand tries.

Nathan-Wong the scored next after making a great break, in what was a perfect half after having to withstand some early Australian pressure.

After the break veteran Portia Woodman stepped twice off her left foot to leave the defence sprawling to add her side's third try.

Nineteen-year-old Alena Saili then sealed the deal for New Zealand when she fended off a defender out wide to score.

Down 28-0, Australia finally got over the line with time almost up when Mahalia Murphy scored late.

New Zealand captain Sarah Goss said it was an amazing feeling to win.

"To beat an Australian team that has so many great players, I'm really happy."

Earlier the Black Ferns overcame hosts USA, 12-7 in a tight semi-final.

They had also beaten Australia 21-14 in pool play, for their four consecutive victory over their Trans-Tasman neighbours.

The New Zealand men's team face a tough quarter-final against England early Sunday evening.