The Impact play host to Costa Rican club Alajuelense in the opening leg of the semifinals on Wednesday night at Olympic Stadium.
The match comes two weeks after Montreal's dramatic second-leg win over Pachuca of Mexico in the quarter-finals, when rookie Cameron Porter's spectacular goal in the dying seconds of injury time sent a Big O crowd of 38,104 into a frenzy.
This time, they play the first leg at home and the second leg in Alajuela, Costa Rica on April 7. As of Tuesday, more than 30,000 tickets had been sold for the first leg.
"Having the first game at home, you want to get a lead," forward Jack McInerney said this week. "The important thing is to keep a shutout.
"We've been focusing on keeping guys back. From the film we've watched, they have seven or eight guys going forward, so we've got to keep a clean sheet. When they're throwing guys forward is probably the best time for us to attack. So we'll play that kind of game. It should be fun and wide open."
Asked to compare Alajuelense with Pachuca, McInerney said they are "pretty much the exact opposite."
While Pachuca played the ball quickly up the wings, Alajuelense prefer a ball control game, building attacks from the back and getting forward in numbers to create scoring chances.
The Impact conceded the lion's share of possession to Pachuca and then scored on counterattacks. It will likely be the same against the Costa Ricans.
"These guys get into your half and play possession," added McInerney. "They're going to get their crosses off and have five or six guys making runs in the box, so box defending will be key."
Montreal is expected to field the same lineup, but without midfielder Justin Mapp. He injured his left elbow during a Major League Soccer match at D.C. United last week.
Quick-footed Dominic Oduro is expected to move into Mapp's spot on the left side, with McInerny drawing in at striker.
"Oduro's a little better out wide," said coach Frank Klopas. "He's more isolated and can get more space."
Klopas will sit out the game after taking a red card for going onto the field after Porter's goal. Assistant Mauro Biello will manage the bench.
Montreal will likely have Evan Bush in goal with the team's new back line of Victor Cabrera, Bakary Soumare, Laurent Ciman and Donny Toia and the new central midfield of Nigel Reo Coker and Marco Donadel. Ignacio Piatti and Dilly Duka complete the attacking midfielders.
The Impact pulled off a surprise in tying the quarter-final first leg 2-2 at Pachuca on a pair of Duka goals. Montreal took the two-game total goals series 3-3 on the away goals rule.
Pachuca may be a stronger club than Alajuelense, but the Costa Ricans pounded D.C., the top seed, 5-2 at home before taking the series 6-4 on aggregate.
"D.C. were in the same situation as us, coming out of pre-season, and I think it got the best of them," said McInerney. "We're better off going into this one after playing a few games.
"They're a good team, but we'll have a game plan and if it works out, we'll be happy."
The winner advances to the final, which is to be played between April 22 and April 29.
The CONCACAF champ goes to the FIFA Club World Cup in December against Champions League winners from all the continents. The defending champion of that competition is Real Madrid.