The Windsor Spitfires and Erie Otters were tied 3-3 through 40 minutes of play during Sunday's title game, before Spits forward Aaron Luchuk potted the eventual game-winner at 5:07 in the third.
The win comes as redemption for a Windsor side that was eliminated during the first round of the OHL playoffs, but then went undefeated as the host club of the 2017 Memorial Cup tournament.
Sergachev earned an assist on the game's opening goal, finishing his tournament with four points in four games (1G-3A), nine shots on goal, two penalty minutes, and a plus-three differential.
His lone marker was a power play winner against Erie during the preliminary round which clinched a spot in Sunday's final.
With the win, the 18-year-old caps off an exciting year in which he was drafted by the Canadiens last June, won bronze at the World Junior Championships with Russia in January, then suited up for stints with the big club in October and April.
Addison meanwhile, concludes a successful week in which he finished tied second among goal scorers tournament-wide -- racking up five tallies in four games -- despite being held off the scoresheet on Sunday.
