TORONTO - Head coach Randy Carlyle has a pretty good idea about what's ailing the Toronto Maple Leafs at home.

"To me, it's mental and that's the operative word that I used in my speaking to (the players)," Carlyle said after Monday's practice. "The issues we have (are) about being strong between the ears."

Toronto dropped to 1-4-0 at the Air Canada Centre after losing a 4-1 decision there Saturday night to the Boston Bruins.

"I think the passion, compete, the relentlessness, the desire — all those are things that have to come on display, night in, night out," Carlyle said. "When you get away from playing with any kind of structure, you start circling and not stopping and doing that, it just multiplies."

On Monday, Carlyle mixed up his line combinations, adding Phil Kessel to the right side of centre Nazem Kadri with Joffrey Lupul on the other wing. Centre Tyler Bozak was between James van Riemsdyk and David Clarkson while Daniel Winnik dropped down to play with Leo Komarov and Mike Santorelli.

"We're not playing our best so obviously they're going to change things up," said Bozak. "We had a rough game as a team last game so we've got to try and spark something here and get back in the win column."

The combination of Carter Ashton, Peter Holland, Richard Panik and Matt Frattin continues to make up the fourth line at practices. Ashton has yet to play this season.

Kadri believes Kessel brings an added element of speed to the line.

"Whenever you get an opportunity to play with those types of players . . . I've played with them in the past so hopefully we can generate some chemistry," he said. "Phil is going to use his speed, I'm going to have to just read off him and (Lupul) is big down low."

Toronto (3-4-1) has failed to earn a regulation win at home over five games at the Air Canada Centre. The lone victory came in overtime against the Colorado Avalanche.

Following Saturday night's game, the Leafs were showered with boos from the home crowd as they left the ice.

"We have to give them something to cheer about," said defenceman Cody Franson. "Sometimes we take that mentality a little too far in terms of trying to put on a show and that's why we play loose to our systems.

"Sometimes less is more and we're going to get back to basics here."

Added Bozak, "When we were playing like we were against Boston, there's no reason they shouldn't be booing us."

Toronto has been outscored 19-10 on home ice. But the Leafs are 2-0-1 on the road and hold an 11-6 scoring edge away from the ACC.

"I certainly don't have an explanation for it but it's pretty obvious we're two different teams," said Kadri. "There is a lot of time left, it's not like we're making our playoff push right now but we've certainly got to get things figured out."

Toronto now has 21 players on its active roster after defenceman Stuart Percy was reassigned to the AHL Marlies on Sunday. Forwards David Booth (foot) and Brandon Kozun (ankle) remain on injured reserve.

"We felt he (Percy) struggled in the two games that we played him in (with seven defencemen)," said Carlyle. "We just felt if we were going to play seven defencemen and continue to play seven defencemen that it was going to be counter-productive for some of our forward group and to Stuart Percy not getting enough minutes."

Toronto hosts Buffalo (2-7-0) on Tuesday with the Sabres coming off a surprising 2-1 win over the San Jose Sharks on Saturday night. Carlyle said his club can't afford to overlook any opponent.

"We're not in any position to take anybody lightly," said Carlyle. "We have to use and muster all of the inner strength that we have to put a performance on that we can be proud of."