Alex Rigsby made 33 saves and Hilary Knight scored as the United States women's team earned a 1-0 victory over Canada in the opener of a three-game series between the rivals.
Knight poked a rebound behind goalie Emerance Maschmeyer with 1:40 left in the second period to quiet the announced crowd of 9,036 at Budweiser Gardens in London.
The Americans have beaten the Canadian women eight of the past 10 times at major tournaments.
Tempers flared in front of the Canadian net as time was running out. The result was minor penalties to both teams, leaving them to close out the period playing 4-on-4.
A sellout crowd of 9,036 was on hand at Budweiser Gardens.
The series resumes Thursday in Toronto and concludes in Detroit Sunday afternoon.