In her first game representing Canada, Johnston, who plays defense for Team Canada, had 3 assists for Canada in a 14-0 win over Greece.
In the first period of her first international game, Johnston assisted on a goal by Silvia Traversa on the powerplay, and by Erika Pouliot. In the second period, Johnston again added a helper, this time on a goal by Melissa Talaro.
Canada won their second game of the tournament 14-0 over Austria. Johnston again hit the score sheet in the game with a single assist on a goal by Fannie Desforges. Canada finished the preliminary round in first place with a 2-0 record, and 28 goals for and none against. Second place Slovakia was also a perfect 2-0, but had a 22-0 goal differential.