United States defeated Japan 7-1 as last year's runners-up aim for redemption ©Getty Images

The United States were dominant in their opening match against Japan at the International Ice Hockey Federation Women's World Championship, winning 7-1 in Brampton in Canada.

The nine-time winners were guided to victory by Alex Carpenter, who scored twice and assisted once as they made a strong start at CAA Centre.

Haruka Toko scored the opening goal for Japan to give them a shock lead before the twice Olympic gold medallists picked up the intensity.

Captain Hilary Knight, who was playing in her new role for the first time, added a goal and two assists.

Aerin Frankel proved to be crucial as the goaltender produced 12 stops in the victory.

In the other match in Group A, defending champions and home side Canada started their pursuit of a third consecutive title with a 4-0 victory over Switzerland.

Natalie Spooner scored and assisted for the 12-time winners and reigning Olympic gold medallists, helping her nation begin its title defence in style.

Ann-Renée Desbiens, the goaltender for the hosts, had a perfect night as she saved all 18 attempts on her net.

Finland also recorded a dominant performance as they routed France 14-1 in Group B, with a hat-trick from Jenniina Nylund.

France swapped goaltenders after the first period as Magaux Mameri had conceded eight goals in 18 shots.

The World Championship is set to continue tomorrow in Brampton, with Japan taking on Czech Republic in Group A. 

Germany meet Sweden and France face Hungary in Group B. 

All five teams in Group A will reach the quarter-finals as it is the designated stronger pool.

The top three teams in Group B will join them.