He'll want a better showing from the Eastern Conference leaders when he returns to the sidelines for a game Wednesday night against the visiting Houston Dynamo.
"We weren't ready from the start," Schallibaum said of the 2-0 loss to the Crew on Saturday night. "But you can't always be at 100 per cent.
"We're not machines. I told them we need to respond."
The Impact (8-3-2), who hold a one-point lead over New York in the East with three games in hand, are 5-0-1 at Saputo Stadium this season. They have yet to lose twice in a row.
The fiery Schallibaum and defender Alessandro Nesta both sat out a game after being ejected in a 2-1 victory in their previous outing in Kansas City.
Both will be back to face fourth-place Houston (6-4-4), a stingy defensive club that has allowed only 14 goals in 14 games. The Dynamo are 2-0-3 in their last five away MLS games.
The Impact have scored 14 times in six league games on home turf, not including their 6-0 win over Toronto in an Amway Canadian Championship game on May 1.
Schallibaum, suspended twice already in his first year in Montreal, said having assistant coach Mauro Biello running the bench in Columbus had nothing to do with the defeat.
He said it may be linked to being rusty from a bizarre schedule that saw the team play seven games in 23 days in late April and early May, followed by a pair of two-week breaks in a five-week span.
And after facing Houston, there's another 10 days before their next game against Colorado on June 29. It is only after that match that they settle into regular weekly matches.
"We had one game two weeks ago and then two weeks with nothing," he said. "It isn't easy for the body.
"It's not an excuse, but it's not easy to find the rhythm. Also, mentally we were not ready."
The time off has at least allowed some injured players to recover.
Forward Daniele Paponi and midfielder Andrea Pisanu both returned as substitutes in Columbus and may start against Houston.
A decision looms on whether to put Paponi in a forward tandem with his former Bologna teammate Marco Di Vaio, who leads the Impact with nine goals. Andrew Wenger has been improving at forward in the Italian's absence, but he was stopped on two glittering chances in Columbus.
"I played well except for the finishing," Wenger lamented. "If I'd have finished, everyone would have said I'm the hero, but that's my job.
"That's what everyone counts on me to do. So, a poor day for me in that respect. But that happens."
Midfielder Justin Mapp is unlikely to play due to a thigh injury and could be replaced on the right flank by Pisanu. And Schallibaum may opt to sit defensive midfielder Collen Warner, who lost a ball to Domenic Oduro on the Crew's second goal, if Andres Romero is fit to play.
Having Nesta back in a veteran central defence pairing with Matteo Ferrari will help, allowing Hassoun Camara to return to fullback.
There were some nasty moments between the Impact and the Dynamo last season that started during Montreal's 4-2 win at home in their first meeting. Houston's Adam Moffat was ejected for an attack on midfielder Felipe Martins and harsh words were exchanged between the clubs.
The Dynamo thrashed the Impact 3-0 in their return to Houston and the teams played to a 1-1 draw in the final meeting of 2012.
That was with Jesse Marsch as coach, but the Impact have taken a large step forward in their second MLS season under Schallibaum, even if his temper sometimes gets the best of him.
The 50-year-old former Swiss international defender says it is coincidence that both times he was tossed were in games against Kansas City. The following games were both against Columbus, including a 1-1 draw in Montreal on April 14.
It seems that teams are playing harder against Montreal than they did during the team's expansion season, when they did well to finish seventh.
Now they're a target.
"We are the team to beat," said Schallibaum. "When you're first, it's like this every time."
Houston reached the MLS Cup final last season, losing to the L.A. Galaxy.
Montreal learned the identity of one of its CONCACAF Champions League opponents this week. The CD Heredia club of Guatemala has joined Montreal and the San Jose Earthquakes in a first-round group. CD Heredia plays in San Jose, Guatemala.Suggest a correction