Samoa and Canada made winning starts to the World Cup on Wednesday, while Scotland held off a brave challenge from Georgia to record their second victory.

Samoa were hugely impressive as they pounded past an outclassed Namibia, with giant winger Alesani Tuilagi grabbing a hat-trick of tries in a 49-12 hammering in Rotorua.

The menacing Leicester Tigers winger gave a Jonah Lomu-like performance to headline Samoa's explosive opening to the tournament.

The physical Samoans, who upset the Wallabies in Australia two months ago, clocked up six tries to two and the fastest first try of the tournament against the outgunned Africans.

The thousands of Samoan supporters in the 13,000 crowd lapped it up in the hot springs resort town, howling with delight as their team ripped in with typical gusto.

But the Samoan victory came at a cost with the loss through injury of goalkicking flyhalf Tusi Pisi and flanker Taiasina Tuifua, with just a four-day turnaround to their all-important Pool D game with Wales in Hamilton.

"The team who wants it more will come out on top," Samoa skipper Mahonri Schwalger said of the Wales showdown.

"The boys are pretty happy with the way they played for our first game and we've got a good squad so we're not worried about injuries. Hopefully, they are not going to be serious."

Canada stunned old World Cup rivals Tonga 25-20 in Whangarei, coming from behind with two late tries to shatter the Sea Eagles' hopes of reaching the World Cup quarter-finals for the first time.

The Canadians trailed by seven points with 13 minutes to go but scores from Aaron Carpenter and Phil MacKenzie broke Tongan hearts with a 25-20 victory, handing them a second Pool A defeat with tough games to come against Japan and France.

"That was awesome, I'm so proud of the boys," said Canada captain Pat Riordan.

"We just said everything we achieve is in our hands so it's up to us to change it (the score) - and we did."

The result extended Tonga's winless World Cup record against Canada and silenced a legion of vocal fans at Whangarei who had harboured high hopes after the Sea Eagles' battling opening defeat to New Zealand.

"We're very, very disappointed," said Tonga coach Isitolo Maka.

"Everyone's really down after tonight but it's not over yet. We have to lift ourselves."

Scotland's 15-6 win over gutsy Georgia in Invercargill came just four days after two late tries saved their blushes in a 34-24 win over Romania and it means they have collected nine points from their two opening games to top Pool B.

Georgian fly-half Merab Kvirikashvili handed his side an unlikely lead against the run of play before Dan Parks levelled the scores.

From there, the two No.10s traded blows with the boot and, with Scotland's pack on top, Parks was destined to be the winner.

But the match left plenty to be desired with a make or break clash with Argentina looming for the Scots on September 25.

"The conditions dictated a lot today," said Scotland skipper Rory Lawson.

"We came up against a big, old Georgian side. It was a workmanlike performance to put them away today.

"I felt we just kept plugging away, put them under pressure and took the points when they were on offer.

"We came looking to get two wins in Invercargill and we got what we came for."

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