Marcus Haber scored in the first minute and Charles Gbeke tacked on a second goal in the 17th minute as Vancouver improved its record to 1-1-0. MLS's Toronto (2-0-0) leads the three-team group from which one team qualifies to represent Canada in the Concacaf Champions' League. Montreal, which won the competition last year, is at the bottom with two losses in two games.
Said Vancouver coach Teitur Thordarson on the Whitecaps' Web site: "In the first half, we were excellent, and deserved the two goals that we scored. In fact, we should have scored more goals before halftime.
"We were a little bit more tactical in the second half, as we dropped one of our strikers back to play in behind his partner up front, in order to try and close the midfield space on Montreal. I thought we did that extremely well, as well as keep possession of the ball during some difficult periods. Overall, it was huge for our side."
Haber struck on a long ball from Gordon Chin shortly after the opening kickoff, and Gbeke, a former Impact player, doubled Vancouver's lead by reaching a cross from Takashi Hirano and heading the ball home.
The Impact, which outshot Vancouver 18-6, nearly equalized in the 31st minute but instead hit the crossbar twice within seconds. Simon Gatti's shot came back from the frame to Roberto Brown, whose shot also beat keeper Jay Nolly but not the woodwork.
It happened yet again a few minutes later when Rocco Placentino's 30-yard free kick rattled the bar.
"Two tactical defensive errors in the first 20 minutes of the game cost us the win, but the players had an excellent attitude as they tried to come back to win," said Impact coach Marc Dos Santos on the team's Web site. "I am proud of the team today because we never panicked and we reacted well to a situation that was unpredictable.
"We had at least 15 scoring chances and three crossbars, but there are days like that, when the ball just doesn't go in. We should not forget that the team was playing a fourth game in eight days."
In the second half, Nolly fended off numerous Montreal attacks and during a five-minute span thwarted the Impact three times. In the 73rd minute he stopped a shot by former teammate Eduardo Sebrango and two minutes later snuffed ex-Rev Felix Brillant. In the 78th minute, Nolly - who played briefly for Real Salt Lake and D.C. United - saved superbly from former United attacker Stephen deRoux. Nolly finished the game with nine saves.
The Impact and Whitecaps meet again next Wednesday at Swangard Stadium in Vancouver. Both teams also play at home against Toronto in June to conclude the tournament.
Canadian Nutrilite Championship
May 20 in Montreal
Montreal 0, Vancouver 2
Goals: Haber (Chin) 1, Gbeke (Hirano) 17.
Montreal -- Jordan, Sakuda, Braz, Pizzolitto, Atte-Oudeyi (deRoux 60); Grande, Placentino (Byers 76), Gjertsen (Brillant 70), Gatti, Brown, Sebrango.
Vancouver - Nolly, Charles, Knight, Hirano, Parke (Thompson 30); Nash, Toure (Lyall 71), Gage, Chin (Moose 58'), Haber, Gbeke.