Benito Floro's side grabbed two away goals to give the Canadians an edge heading into next week's second leg.
Canada opened its World Cup qualifying campaign with a 2-0 victory at Dominica on Thursday.
Striker Cyle Larin scored the first goal and drew the penalty that led to the second as the Canadians looked disjointed at times but ultimately in control over the island nation.
Larin opened the scoring in the fifth minute, when he slipped behind the Dominican back line along the right side and slid a low side-footer under the onrushing goalkeeper.
The Canadians wouldn't find the back of the net for the rest of the first half, however, as Dominica packed the defensive third quite effectively in the face of overwhelming possession by the visiting side.