Therrien shuffled Max Pacioretty off what used to be the team's top line and put him with rookies Alex Galchenyuk and Brendan Gallagher on Monday as the club prepared for a two-game trip to Florida.
The move came after a blowout 6-0 loss on home ice to the rival Toronto Maple Leafs on Saturday night.
It will now be up to tough winger Brandon Prust to try to get centre David Desharnais and right-winger Erik Cole going after a sub-par start to the NHL season.
"For the Desharnais line, we don't have the results were looking for," said Therrien. "We gave those guys a lot of chances.
"I didn't see much chemistry and that's why we wanted to make a switch. Hopefully we'll get better results."
Last season, Pacioretty (33 goals and 65 points), Cole (35 goals) and Desharnais (60 points) led the team in scoring. This year, Pacioretty is without a goal in seven games, while Desharnais has five points and Cole has four in 11 games each.
Pacioretty was already the centre of attention for a third-period incident against Toronto in which Grabovski allegedly bit him on the wrist during a skirmish. The NHL opted on Monday not to fine or suspend the Leafs centre due to insufficient evidence.
Now 24-year-old Pacioretty will be the veteran on a unit with 20-year-old Gallagher and with Galchenyuk, who turns 19 on Tuesday.
"It has nothing to do with the last game," said Therrien, who shuffled combinations liberally during that contest. "Those kids have a lot of speed, and having a guy like Pacioretty will make them tough to contain.
"Prust did a phenomenal job with the young kids. He's tough to play against and maybe that's what Desharnais and Cole need: a true leader on the ice."
Galchenyuk, the third overall pick in the June draft, has a goal and six assists in 11 games and has been dangerous on attack on nearly every shift. The feisty but pint-size Gallagher has four goals and two helpers in 10 games.
"I've relieved Prust of his babysitting duties and hopefully now Galchenyuk can get a goal on his birthday," said Pacioretty. "It's something different.
"The chemistry didn't seem to be there on our line. We weren't helping the team win. I know I can play better. I've been under-achieving and if it takes a couple of young guys to get me going, great."
The team's most effective trio of Tomas Plekanec at centre with Rene Bourque and Brian Gionta is intact, while Lars Eller remains on the fourth line with Travis Moen and Colby Armstrong.
The Canadiens had been playing decent hockey until Saturday, when they went to pieces after conceding a first-minute goal to Toronto's Leo Komarov.
But the loss left them winless in three games, following a 2-1 loss to Boston in which they wasted a third-period lead and a 5-4 shootout loss in Buffalo that they led 4-2 in the third.
"It was bad game for the whole team, but we still put up 37 shots," Pacioretty said of the Leafs contest. "We made some terrible decisions and the puck ended up in our net.
"It was just a flukey game. But we still had to correct some things and we worked on that (Monday)."
The Canadiens play the Lightning in Tampa, Fla., on Tuesday and the Florida Panthers on Thursday before returning home to face the Philadelphia Flyers on Saturday night.
The Tampa Bay game will be their 12th of the lockout-shortened season, or one-quarter of the way through the 48-game schedule.
Therrien gave his 6-4-1 club a passing grade thus far, with reservations.
"I wished to have a bit better record, honestly," he said. "Last week we played a solid game against the Bruins, a decent game against Buffalo and obviously Saturday was a tough one.
"But looking all around and how we've played since the start of the year, I'm satisfied. We're still in good position."
Eight of their first 11 games were at home.
The Lightning (6-5-0) scored 37 goals as they started the season 6-1-0, but have only six goals in their last four, all losses. They are coming off a weekend in which they had a game Saturday in Boston postponed due to snow and then were beaten 5-1 by the Rangers in New York.
Pacioretty has six goals and nine points in eight career games against Tampa Bay.
The New Canaan, Conn. native had a precautionary tetanus shot after the suspected biting incident with Grabovski because he was cut.
He was in his fourth game back after missing four games while recovering from an emergency appendectomy.