Toronto was too passive in the 2-1 loss to Houston. Playing in two flat lines of four in the midfield and backline had helped shore up the defence on the road but only served to give the visiting Dynamo time on the ball to probe away.
Wednesday represents an opportunity for Toronto to showcase a more offensive approach at home as its hosts the Montreal Impact in the second leg of the Amway Canadian Championship semifinal.
"We're down a goal. So it's on us to go make the game a little bit," said Vanney. "For me I like that. I think that's what this team needs right now."
Vanney says his players found themselves spread too thin in the first half against Houston, too far apart to connect properly once they got the ball.
The Toronto coach wants his team to be more aggressive and proactive Wednesday.
"We don't have to be the exact same team on the road and at home," he said. "We can alter that. We have some high-quality players, they need to get more touches on the ball (and) not be in defensive mode as long."
Montreal won the first leg 1-0 thanks to a 68th-minute strike by Jack McInerney at Saputo Stadium and is ready for a Toronto pushback.
"I have a feeling it's going to be fairly open on their side," Impact goalie Eric Kronberg said. "They're going to probably need to push numbers forward to get that goal so hopefully we can catch them on the counter(-attack)."
Both teams need to manage their minutes. It's the third game in a week for both sides, with weekend league matches looming.
Toronto's Jozy Altidore and Sebastian Giovinco sat out last Wednesday's game in Montreal while fellow designated played Michael Bradley saw 74 minutes of action.
Bradley never seems to want a rest but Vanney could sit him out the second leg just to save his body. Giovinco is available having recovered from a sore heel sustained during a physical day at the office against Houston. The bullish Altidore might get the nod given Toronto's need for goals.
Vanney hinted he may opt for a defensive midfielder, to shield the backline while allowing other midfielders to roam forward.
"We're prepared for all options," said Montreal coach Frank Klopas. "But again, we have to worry about our team. That's the most important thing."
Chris Konopka is expected to continue in the Toronto goal, with Joe Bendik recovering from a foot problem. Defenders Steven Caldwell (leg) is out while Mark Bloom in questionable. Vanney says Bloom's quadriceps issue has healed but he is now experiencing back spasms.
While the Houston game drew 30,226 to the newly renovated BMO Field, Wednesday's crowd is likely to be more modest. Toronto has some 20,000 season ticket-holders, but the Amway Canadian Championship games come as part of their package and so attendance may depend on the weather (the game-time forecast call for 10 degrees and no rain).
The semifinal series winner will play either the Vancouver Whitecaps or FC Edmonton for the right to represent Canada in next year's CONCACAF Champions League.
Montreal made it all the way to the Champions League final this year before losing to Mexico's Club America.
Montreal (0-3-2) lost 2-1 to visiting Portland on the weekend while Toronto (3-5-0) fell to Houston.
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