All Blacks coach Steve Hansen made 11 changes from the side that defeated South Africa 23-13, as the roof-covered Oita Stadium on Kyushu Island made its tournament debut.

The three Barrett brothers - Jordie, Scott and Beauden - became just the second trio of siblings to start a World Cup match, following Elisa, Manu and Fe'ao Vunipola of Tonga in 1995, and the All Blacks set their stall out quickly.

Within five minutes, captain Kieran Read was denied on the line, with French referee Roman Poite somewhat controversially awarding a penalty try.

It was the worst possible start for Canada, world-ranked 22, and New Zealand's record of never having lost a World Cup pool match wasn't under threat.

A delightful cross-kick from flyhalf Richie Mo'unga landed perfectly for Jordie Barrett to score in the ninth minute, and Mo'unga repeated some handy boot-work for Sonny Bill Williams' five pointer in the 18th minute.  

Williams then made a superb line-break to gift Beauden Barrett a try, and the bonus point was already in the bag after 35 minutes.

Facing a 28-0 deficit at halftime, if Canada were hoping the pressure would ease in the second half they were sorely disappointed, as Rieko Ioane crossed the line within a minute of the restart.

Scott's try in the 44th minute completed the Barrett family hat-trick and the lead had ballooned to 42-0.

The procession continued thanks to Shannon Frizell and a try-scoring double for Brad Weber.

Perhaps the only disappointment for the All Blacks was a failure to score in the final 20 minutes, and the points they left out on the pitch – with brothers Scott and Beauden both dropping ball as the tryline beckoned.

However, these are only minor blemishes on an awesome, nine-try attacking performance, while Mo'unga kicked an impressive eight from nine conversions.

New Zealand now have a quick turnaround with lowly Namibia next up on Sunday (October 6), as Canada's painful tournament moves to Kobe Misaki Stadium and the brute force of South Africa next Tuesday (October 8).

In Pool C, France spluttered to a 33-9 victory over the United States, with the scoreline flattering the pre-match favourites.

The game at Fukuoka Hakatanomori Stadium started well for the French, with a delightful kick from Camille Lopez creating a try for Yoann Huget in just the sixth minute.

But the US refused to panic, and AJ MacGinty kept them in touch with a penalty.

Lopez was again the catalyst for a five-pointer, with his cross-kick collected by Alivereti Raka to score.

Another MacGinty penalty sent the US just 12-6 behind at halftime and the result in the balance.

When MacGinty slotted three more points on 64 minutes, a shock was on the cards.

France lacked cohesion, dropped too much ball, and were incredibly grateful when Gaël Fickou scored a try with 14 minutes remaining.

Further five-pointers for Baptiste Serin and Jefferson Poirot secured a bonus point for the French, but they know performance levels will have to increase for their next game against Tonga on Sunday (October 6).

The US will be underdogs again next Wednesday (October 9), against Argentina.