The Toronto Maple Leafs haven't won a playoff series since 2004. That drought is in danger of being extended thanks to missed opportunities and mental mistakes against the Montreal Canadiens, who pushed their series with the Leafs to a Game 7 with an overtime win on Saturday night.

"We had plenty of chances. It's a game of inches out there. And we couldn't get it done," Toronto star Auston Matthews said after Montreal's 3-2 overtime win in Game 6, their second straight OT victory against the stumbling Maple Leafs.

For the second time in as many games, the game-winning goal was gifted by a Toronto turnover. In Game 6, defenseman Travis Dermott lost the puck in his own zone, leading to Jesperi Kotkaniemi's fluttering deflected shot to slip past goalie Jack Campbell at 15:15 of overtime. It was the Canadiens' second shot of the extra period, while Toronto had 13 turned away by goalie Carey Price (41 saves).

Many of the scoring chances in overtime were generated by the Maple Leafs' top line with Matthews and Mitchell Marner. But they have one goal combined in the series.

"I thought they worked really hard. Obviously, they didn't get enough done," Toronto coach Sheldon Keefe said.

Suddenly the Maple Leafs, a franchise defined by its postseason heartbreak, are in danger of a first-round elimination in their quest to win the Stanley Cup for the first time since 1967.

"Don't worry about what the fans are saying. It doesn't matter," forward Nick Foligno said. "This happens for a reason. Sometimes this is what catapults you. It's hard for the fan base to hear right now, but we're going to come with the mindset that we're going to win a hockey game."

That overtime mistake ended the game, but it wasn't the only Maple Leafs' gaffe that shifted Game 6 to Montreal. Toronto came out flat in the first period, getting outshot 15-9 as the Canadiens fed off their home crowd of 2,500 fans, the first time spectators have been allowed in Bell Centre this year.

"We just didn't come ready to play at the start of the game. We really do have to start on time because it's getting said a lot, and it's not good enough," Marner said.

In the third period, Toronto used a coach's challenge on Montreal's first goal of the game, hoping that Canadiens forward Tyler Toffoli's presence in the goal crease would nullify Corey Perry's power-play goal. They lost the challenge and earned a minor penalty for delay of game. Just 19 seconds later, Marner cleared the puck over the glass for another delay of game penalty. Toffoli scored on the subsequent 5-on-3 power play.

"We felt it was worthy of a challenge," Toronto coach Sheldon Keefe said. "There's some precedent there, with Toffoli standing there in the crease and the goalie's trying to get back into his crease and he can't. We thought there was some precedent there. We thought given what was happening in the game, the significance of the goal, I thought in the moment it was worthy of the challenge and having the confidence in the penalty kill that they could get it done. But obviously, it ended up 5-on-3."

Maple Leafs veterans Jason Spezza and T.J. Brodie scored in the third period to force overtime, giving Toronto some semblance of positive momentum as it heads home.

"That last 10 minutes or so just shows that we don't quit," Campbell said.

But Monday night's Game 7 has the top-seeded Maple Leafs looking at another potential playoff disaster. They entered the series as one of the favorites to win the Stanley Cup. They lost star center John Tavares to injury in a Game 1 loss, inexplicably won the next three games, but are one loss away from elimination.

"You work hard in the beginning of a series to give yourself a crack at putting them a way. It's coming up on three [for us]," Foligno said. "I believe in this group. For what we're trying to accomplish here, I think it's just staying in the moment. That is the best thing you can advise anybody.

"In a Game 7, you rise to the occasion because you're in the moment and there may not be a tomorrow."