The Marquis powered to a 2-1 victory over the River Kings on Friday night to take a 1-0 lead in the first-round LNAH series.
Francois Fortier opened the scoring for Jonquiere with a powerplay marker at 19:11 of the first.
Nicolas Larocque-Marcoux brought the Kings to within a goal with 2:17 to play in the contest.
Cornwall outshot Jonquiere 22-21. Game 2 goes Saturday night in Cornwall.