Di Vaio hasn't scored in five games, although the stocky forward seems to coming closer each time out for the struggling Major League Soccer expansion team.
"The pressure is something I put on myself," he said Tuesday. "To score for the team, not for myself, that's the pressure I feel."
He will try again when Montreal (6-12-3) plays host to the New England Revolution (6-8-4) on Wednesday night at Saputo Stadium. The Impact expect to debut new Swiss signing Dennis Iapichino at left back.
Di Vaio, who turned 36 on Sunday, joined Montreal from Bologna in Italy's Serie-A. He had been a prolific scorer over the past two decades with several clubs, finding the net 195 times in 490 matches. He said he is happy with the Impact, but not pleased with his lack of finish in front of goal.
He is Montreal's first designated player — one who earns more than the maximum under the league's salary cap — but little has gone right since his arrival.
In his debut match June 27, Montreal lost 3-0 at home to rival Toronto FC. In five games, the team has one win and four losses and has been outscored 12-4. In the three games before he joined the team, they went 2-1-0 and scored nine goals.
"There's a good understanding of Marco now and he's fitter and sharper," said coach Jesse Marsch. "I said from the beginning it was important to be smart about the expectations.
"He's fit in really well. I think our group likes playing with him. I told him I'd be more concerned if he wasn't getting chances. They're going to come, there's no doubt. He has a track record of scoring so many goals that it's only a matter of time."
Montreal hoped he would form a scoring partnership with compatriot Bernardo Corradi, but the big forward tore a knee ligament in training and is gone for the season.
Di Vaio has yet to play with any of the club's Italian contingent because central defender Matteo Ferrari is out with a thigh injury, while newly signed defender Alessandro Nesta won't make his debut until Saturday in Houston at the earliest. Nelson Rivas, who is Colombian but played at Inter Milan, is also injured.
Injuries in the central defence and some careless play on set pieces has much to do with the goals Montreal has conceded of late, but they would likely have more points in the bank had they scored more.
Captain Davy Arnaud said they are not relying on Di Vaio to be a saviour.
"Good teams spread the scoring among their players," he said. "It's more than one player.
"We've done that for the most part. Marco's a guy everyone expects to score goals and it's important for him to get his share of goals. I don't doubt he will. But as a group, we don't look at who is scoring. It's all about winning games at this point."
The Impact are clinging to eighth place in the Eastern Conference, one point behind New England, which has three games in hand. Houston is in fifth spot, so there is a chance this week to pick up important points in the conference.
"We've let so many points slip away that every game is important for us now," added Arnaud.
Marsch looks set to make extensive changes against New England, taking right back Zarek Valentin and midfielder Collin Warner out.
Iapichino at left back would bump Jeb Brovsky to the right side, while playing Sanna Nyassi in midfield on the right side would pushes Arnaud over to the left. Justin Mapp moves into the centre, behind Di Vaio, while Felipe drops back into Warner's spot next to Patrice Bernier in the second line of a 4-2-3-1 formation.
"It's fresh legs for a busy week," Marsch said of the possible changes.
The last time Mapp played in the middle was in Montreal's 2-1 win over Columbus on July 8.
Marsch said Nesta will not be on the 16-man roster, but will likely be included Saturday, although it remains to be seen if the former AC Milan star will play. He said Ferrari and Rivas will resume full training next week.
New England, meanwhile, begins a three-game road trip without forward Jerry Bengtson, who has joined the Honduras squad at the London Olympics.
The Revolution may also be missing central defender Stephen McCarthy, who had a suspected concussion after a collision with Toronto's Ryan Johnson in a 1-0 loss on Saturday.
The Impact have loaned little-used forward Miguel Montano to Deportivo Cali in his native Colombia. That opens an international roster spot that is expected to be filled before the end of the month.
Montano was involved in an incident in June in which he tweeted that Montreal is a racist city after a subway ticket seller refused to serve him in English. He later retracted the comment.