The Rick DiPietro-less Islanders dropped out of the top eight in the NHL Eastern Conference with an 8-5 loss to Florida on Saturday that put them in a tie with Montreal and Toronto for ninth place.
The Canadiens' posted a 3-2 shootout win over the Leafs.
With 78 points, those three clubs are one point behind the New York Rangers, who blitzed Boston 7-0, and two behind the defending Stanley Cup champion Carolina Hurricanes, who chased Martin Brodeur in a 7-2 win over New Jersey.
The Isles have 11 games left, Toronto and the Rangers have 10 while Montreal and Carolina have nine still to play. All five clubs were idle Sunday.
Of the five, none has a tougher schedule than the Leafs, whose next six games are against teams ahead of them in the standings.
It starts Tuesday when they host second-place New Jersey. Then they are back-to-back with first-place Buffalo, at home against Carolina, in Atlanta and then back home against Pittsburgh.
"We've got some tough teams to play," said Leafs forward Kyle Wellwood. "But that's going to make it all the more difficult and exciting, because I feel we'll play our best against the tough teams."
The Leafs get one more crack each at the Rangers, Islanders and Canadiens in final week of the season.
"These games, regardless of who you're playing, they're all a lot tougher," said Leafs coach Paul Maurice. "It'll be an ugly dog fight right until the end."
Injured defenceman Tomas Kaberle may be back to face New Jersey for the first time since he was badly injured on a late hit into the boards by the Devils' Cam Janssen on May 2.
Toronto burned two points with a 5-1 loss to 14th-place Washington on Friday night. On the same night, Montreal fell 6-3 in Pittsburgh.
Montreal rookie Jaroslav Halak replaced David Aebischer in goal and had a huge game against Toronto, stopping 37 of 39 shots and three more in the shootout.
It was the level of goaltending the Canadiens will need down the stretch with starter Cristobal Huet likely out for the rest of the regular season after hamstring surgery.
Their schedule is relatively light, with only four games left against teams currently ahead of them.
They have a chance to bury Boston in back-to-back games this week - Tuesday in Montreal and Thursday in Boston - or let the 12th place Bruins back in the playoff race. The Bruins are five points back with 11 games to play.
They have another date with the Bruins on April 3 and have two games left against the Rangers. They finish the season April 7 in Toronto.
The Canadiens have won three of their last four after a four-game losing streak that looked to have compromised their playoff chances.
"If we had lost two games (on the weekend) it would have been tough because of the standings, but the way we're playing now is a lot better," said coach Guy Carbonneau. "We played (well) for 60 minutes and that's what you need to be successful at this time of the year."
A key play in the race may have occurred last Tuesday in Montreal, when DiPietro opted to skate out near the blue-line to play a puck and collided with the onrushing Steve Begin. The Isles have lost two in a row with Mike Dunham replacing DiPietro, who is said to have a neck injury.
The Islanders have tough games ahead Tuesday at Tampa Bay and Thursday at home against Pittsburgh. They also must face the Rangers and Devils twice each before the end of the season.
The Rangers are 6-1-3 in their last 10 games and have a relatively light finish after their home game Monday against Pittsburgh.
They face the Canadiens, Islanders and 15th-place Philadelphia twice each, with no games left against the conference leaders Buffalo, Ottawa, Atlanta or New Jersey.
Carolina came off a 3-2 loss to the Devils to blitz New Jersey on Saturday. They get Washington at home on Tuesday before playing host to western power San Jose on Saturday.
The Hurricanes' only game against the four teams they're battling for a playoff spot is March 27 in Toronto. They have two games each left against Florida and Tampa Bay.
The Canadiens-Tor matchup had the feel of a playoff game, with a large contingent of Toronto fans at the Bell Centre trying to drown out the locals.
There was a lot of hitting and shoving matches and even a scrap between Darcy Tucker and Francis Bouillon, but rookies Halak and Andrei Kostitsyn made the difference for Montreal.
Pavel Kubina tied the game in the third after Wellwood scored for Toronto and Kostitsyn and Saku Koivu scored for the Canadiens in the opening two periods.
Montreal shot first in the tie-breaker and, after Mats Sundin put Toronto ahead, Koivu tied it on Montreal's third shot and Halak stopped Yanic Perreault. Kostitsyn buried the fourth shot and Halak stoned Tucker to secure the win.
"We definitely had enough chances to win the hockey game in regulation," said Sundin. "But we'll take the point and we can't dwell too much over this loss."