The Canadians will now meet the United States in Thursday's final, with a chance to win it all on home ice for the second time since 2015.
Juulsen, who is a Habs first-rounder (2015), picked up an assist in the semifinal win, and now has two through six games during the event. He has also fired nine shots on goal, earned a plus-5 differential and served four penalty minutes.
Russia 3 - United States 4 (SO)
Earlier in the day, Sergachev and the Russians fell 4-3 in a shootout to the United States.
The Habs prospect was held off the scoresheet, but fired four shots on goal.
The 18-year-old rearguard, who was the Canadiens' first round pick at the 2016 NHL Draft, has scored one goal in six World Juniors games to date. He has registered 15 shots on goal and posted a plus-3 differential to go with four penalty minutes.
The gold medal and bronze medal games will both take place at the Bell Centre on Thursday.
