New Zealand grabbed their first bonus point of the 2019 Rugby World Cup on Wednesday, racking up nine tries in a 63-0 dissection of Canada.

All three Barrett brothers -- Beauden, Jordie and Scott -- scored tries, while man-of-the-match Richie Mo'unga kicked eight conversions as the Pool B favorites clinched the bonus point before halftime at a humid Oita Stadium.

With head coach Steve Hansen making 10 changes to the starting XV following their 23-13 defeat of South Africa on Sept. 21, the second-string All Blacks remained on cruise control throughout the game against an overmatched Canada.

But the three-time champions were sloppy at times, squandering multiple try-scoring opportunities as they struggled to hold onto the slippery ball, while also gifting the Canadians a stolen lineout.

Captain Kieran Read said the humidity under the Oita Stadium roof posed a major challenge, but one the All Blacks must be prepared to tackle again, with the venue set to host two quarterfinals.

(Richie Mo'unga (R) of New Zealand tackles Ciaran Hearn of Canada.)

"We were dripping wet as soon as we ran out to start the game," Read said. "But (it's) something to work on in the knowledge we'll probably get these conditions later on."

After sticking with No. 1 Atunaisa Moli for the full 80 minutes, Hansen singled out the prop for praise after the game.

The coach said Sonny Bill Williams had also made a strong case for first-choice selection after scoring a try and creating another from inside center.

"(Williams has) always been pushing. I mean we've (been) very, very blessed in the midfield with the talent we've got," Hansen said.

New Zealand took just four minutes to open their account, powering their way to the posts from a five-meter scrum.

With No. 8 Read about to pick up the ball and score, Canada scrumhalf Gordon McRorie came around and tried to steal it, prompting referee Romain Poite to award the penalty try.

Flyhalf Mo'unga created the All Blacks' second try with a superb cross-field kick that set up winger Jordie Barrett to score in the corner. Mo'unga added the extras for a 14-0 lead.

(Peter Nelson of Canada runs with the ball.)

Canada came close to crossing midway through the half, with flyhalf Peter Nelson thrilling the fans in red with a zigzagging run toward the New Zealand line before being pulled down inches short by fullback Beauden Barrett.

The chance came amid the best stretch of the half for Les Rouges, who kept their fancied opponents pinned inside the 22 for several minutes.

Canada captain Tyler Ardron praised his team for keeping up the fight against the world's No. 1 side, but said they gave away the ball too easily.

"I thought that when we had our chances, we took advantage of some of them, so it's tough when you give them the ball. Then they're pretty tough to defend," Ardron said.

New Zealand almost secured the bonus point in the 29th minute, but a powerful run from Scott Barrett culminated with the lock dropping the ball over the line while trying to ground it with one hand.

The crucial fourth try came six minutes later when Williams chipped through for Beauden Barrett to score under the posts. Mo'unga struck the conversion to send the All Blacks into halftime with a 28-0 lead.

Replacement Brad Weber scored a pair in the second half, while Rieko Ioane, Scott Barrett and Shannon Frizell also crossed for tries after the break.

No. 4 Barrett made amends for his first-half gaffe when he broke the Canadian line and touched down in the 44th minute.

His brother Beauden created the try of the night in the 49th minute, wriggling through a gap and sprinting downfield before offloading to Weber just short of the line.

The win moves New Zealand to second in the pool behind Italy, who have two bonus-point victories from as many games. The All Blacks face Namibia in Tokyo on Sunday.

Kingsley Jones' Canada remain winless and will meet South Africa for a third-straight match against Tier 1 opposition next Tuesday in Kobe.

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