A good showing by the top pick in the Major League Soccer SuperDraft could lead to more starts through the final stretch of the season now that Di Vaio's future is in the hands of a tribunal investigating a massive betting and match fixing scandal in Italy.
"It's like any other game," said 21-year-old Wenger, who returned last week from a hamstring injury. "The pressure is on the team to put another win together and keep moving forward."
Montreal (8-13-3) is four points ahead of Philadelphia (7-10-2) in Eastern Conference standings, but the Union hold five games in hand.
Prosecutor Stefano Palazzi on Friday requested a one-year suspension for Di Vaio, formerly of Serie-A club Bologna, for allegedly failing to report fraud in a suspected match-fixing incident in a game against Bari in 2011.
Di Vaio said last week he wasn't worried about the hearings in Italy because he did no wrong, but the prosecutor's aggressive stance suggests there is cause for concern. Reports said the tribunal hopes to make a decision by the end of next week.
The 36-year-old is the Impact's highest paid player at US$1.9 million and its first designated player, or one paid more than the MLS maximum of $350,000. He scored his first MLS goal in a 3-1 win over New York last week and was hoping to get on a roll over the final 10 matches of the regular season.
"It's unfortunate timing, but we're confident that when he comes back we can continue from where he left off," said coach Jesse Marsch. "We know we have a good bench, so when Andrew steps in and Sanna (Nyassi) comes on the field, we have guys that can help us attack and are dangerous."
Di Vaio left this week for the hearings in Italy and was expected back Sunday. Marsch said he may now return Saturday afternoon, although there are no plans to use him in the game after that much travel.
The coach would not speculate on what the team will do if Di Vaio is suspended.
"That would be bad," he said. "It's hard to predict what's going on over there.
"I know it's bit of a witch hunt. So there's not really anything I can comment on because I don't now enough about what exactly is going on and who is involved. It's futile to talk about it until it's actually reality."
Di Vaio was the key figure in the expansion club's recruiting campaign. It was while meeting with Di Vaio that they acquired defender Matteo Ferrari, who brought in his friend Bernardo Corradi, the team's scoring leader until his season ended with a knee injury.
And Alessandro Nesta, the former AC Milan and Italy defender, signed with Montreal largely because his old friend Di Vaio was there.
Palazzi also recommended a 3 1/2 year ban for Juventus and Italy defender Leonardo Bonucci over a match in 2010, and one year for Juve's Simone Pepe. He called for Bologna to be docked two points in the standings. Juventus coach Antonio Conte had a plea bargain turned down this week and faces a long ban.
In all, 13 Italian clubs and dozens of players and training staff are under investigation.
The Impact want to stay focused on making the playoffs, starting with a win over Philadelphia.
The Union were 4-1-0 in league play in July, including a 2-1 win at home against Montreal in which the Impact tied the game in the 89th minute only to lose on a Carlos Valdes goal in injury time.
There have been big changes since then, starting with the return of Wenger, Ferrari and Nelson Rivas from injuries and Nesta's debut against New York. Montreal expects to start a three-man back line of Ferrari, Nesta and Rivas, with Hassoun Camara playing in an advanced right back role.
The Union may debut six-foot-four central defender Bakary Soumare, a former MLS all-star with the Chicago Fire who was recently signed from French club Boulogne.
Montreal wants to build on a home record of 7-3-2. The New York match was their first sellout since returning to revamped Saputo Stadium. On Friday, about 2,000 tickets remained for the Philadelphia clash.