But five goals without reply in the final third of the match saw the defending champions through by a 6-2 scoreline in the second Group A match to be played at the Espoo Metro Areena watched by a crowd of 4,046.

That means the US, seeking a fifth consecutive world title, moved up to the shoulder of the other tournament favourites, Canada, who had opened with a 6-0 win against Switzerland.         

The tournament had got underway with a Group B match in which Laura Kluge scored the lone goal in the shootout to lift Germany to a 2-1 upset win over Sweden.

Japan finished day one top of Group B after a 3-0 win over France.

Finland had only beaten the US once in the World Championships, winning a round robin match 1-0 in overtime in 2008.

But after goals from Elisa Holopainen and Petra Nieminen it looked as if another rare triumph was in the offing.

That aspiration was swifly crushed, however, as the US scored through captain Kendall Coyne Schofield, Hilary Knight, Alex Carpenter,  Melissa Samoskevich, Brianna Decker, and Annie Pankowski.

Elisa Holopainen and Petra Nieminen replied for Finland.

"I think we played a really good first two periods, but with the third one, we can't be happy," said Finnish captain Jenni Hiirikoski.

The US knew they had survived a scare.

"It was a tough start," said Schofield.

"It's not the way we want to start a tournament and represent Team USA.

"But I think coming out in the third, we proved the game we can play.

"At the end of the day, we need to play a complete 60 minutes."

The Opening Ceremony had featured an all-female figure skating exhibition and local ice hockey players.

Emma Terho, the five-times Olympian and now International Olympic Committee member, and Hungary's Zsuzsanna Kolbenheyer, an IIHF Council member and head of the IIHF Women’s Committee, welcomed the world to Espoo and declared the event open.