Sundin scored his second goal of the game 3:20 into overtime as the Maple Leafs squandered a three-goal lead before pulling out a 4-3 victory over the Los Angeles Kings.
"I'm the captain," Sundin said. "There is a responsibility to make sure we have a good dressing room, to make sure we play to our ability, which we haven't been. I put pressure on myself."
Sundin put his own rebound past Jamie Storr for his 53rd career game-winning goal and 11th in overtime. He moved into a tie with Steve Thomas, Jaromir Jagr and Sergei Fedorov as the top regular-season overtime scorers in NHL history.
"You've got to give credit to Sundin," Storr said. "He's a great player, he makes great plays and he got his own rebound, so it was a great play by him."
Mikael Renberg worked hard to earn assists on Toronto's first two goals, winning the puck along the boards to set up tallies by Sundin and Jonas Hoglund. Renberg has eight points in his last seven games.
Sundin scored 3:45 into the game after Darcy Tucker's shot from the left faceoff circle missed the net. Sundin used his skate to control the puck behind the net, then tucked it between former Maple Leaf Felix Potvin's skate and the left goalpost.
"Tonight, we were off to a good start," Sundin said. "We tried to play with a little more edge."
Just under eight minutes after Sundin's goal, Renberg won a battle with another former Leaf, defenseman Mathieu Schneider, skated to the outside of the right circle and slid a pass to Hoglund, who rifled a shot past Potvin.
"This was a game that we had to win, and we won it," Renberg said. "Now we can breathe a little bit."
Changing goaltenders provided a spark for the Kings, who scored all three of their goals in the third period. Storr replaced Potvin to start the third period after Potvin surrendered three goals on 18 shots.
"Anytime a coach does that, he's looking for more from everyone," Schneider said. "And he got that tonight."
With 5:13 left, however, Deadmarsh sent the game to overtime, deflecting Modry's shot past Ed Belfour for the game's lone power-play goal.
"You can tell we're a fragile team," Sundin said. "In the third, we stopped skating and waited for the period to end, and you can't do that. We made a couple of mistakes and they were back in the game."
Deadmarsh, who leads the Kings with nine goals, ended a four-game drought. Modry has scored all six of his goals in the last seven games.
The power play that sent the game to overtime was only the Kings' second in a relatively penalty-free game that saw Toronto go 0-for-3 with the man advantage.
Ed Belfour made 24 saves for his fourth win of the season. His biggest save of the night came two minutes into overtime, when he got enough of Derek Armstrong's shot to send it over the net.
Toronto has been outshot in all five of its victories this season and won for just the second time in seven one-goal decisions. The Maple Leafs have won three of four games against Pacific Divison foes.
Los Angeles fell to 1-2-0-1 on an eight-game road trip extends through November 21.
"I'm not happy," Potvin said. "But we got one point and it was a big one."
Toronto's Tie Domi played his 800th NHL game, while linesman Danny McCourt worked his 1,500th.