Knight passed the puck, Kendall Coyne scored the go-ahead goal at 11:29 of the second period on a one-timer and the United States rallied to beat Finland 3-1 to remain perfect when opening an Olympic tournament.
Monique Lamoureux-Morando and Dani Cameranesi also scored as the Americans improved to 6-0 all-time in Olympic openers. They also improved to 7-0 against Finland in the Olympics, though the world's third-ranked team made the defending world champions work hard in a chippy game.
Hovi Venla scored on a wrist shot from the slot with 5.8 seconds left in the first period, giving the Finns the lead and a reason to celebrate going into intermission.