WASHINGTON — Don't count out the Washington Capitals, no matter how big the deficit, no matter how dire the circumstances.

Nicklas Backstrom completed a hat trick by scoring only 31 seconds into overtime, helping the top-seeded Capitals finish a wild comeback to beat the Montreal Canadiens, 6-5, last night and even their first-round Eastern Conference playoff series at a game apiece.

Montreal led 2-0 after its first two shots, prompting Washington to yank goalie Jose Theodore, and then went ahead 4-1. But with Alex Ovechkin producing a goal and three assists, the Capitals rallied.

Rookie defenseman John Carlson tied it at 5-all with 1:21 left in regulation, and Backstrom's wrister past Jaroslav Halak won it.

"We have that side of our team: We never give up," Backstrom said. "The second period was kind of embarrassing for us. But we bounced back."

Game 3 is tomorrow in Montreal.

Andrei Kostitsyn had a hat trick for the eighth-seeded Canadiens, and Tomas Plekanec put them ahead 5-4 with 5:06 left in regulation. But Carlson picked a fine time for his second NHL score — he had one in 22 regular-season games.

BRUINS 5, SABRES 3

BUFFALO, N.Y. — Michael Ryder and Zdeno Chara scored 2 minutes apart in the third period, helping Boston rally past Buffalo to the first-round, Eastern Conference playoff series at 1-all

The Sabres not only squandered a lead entering the third period for the first time this season but also lost leading scorer Thomas Vanek, who didn't return after he hurt his left foot in the first period.

KINGS 3, CANUCKS 2

VANCOUVER, British Columbia — Anze Kopitar scored on a power play 7:28 into overtime and Los Angeles overcame a two-goal deficit to beat Vancouver, tying the Western Conference series at a game apiece.

With the Canucks penalized for too many men on the ice after a sloppy line change, Kopitar got his own rebound in the slot and fired a quick shot that hit Roberto Luongo and then bounced in off the butt end of the goalie's stick.