Alfredsson scored twice, including the game winner on a power play with 4:59 remaining, to lift Ottawa to a 3-2 victory over the Toronto Maple Leafs on Thursday night.
The Senators' captain put a wrist shot over Vesa Toskala's right shoulder into the top left corner for his third goal of the season and helped Ottawa regain the lead after blowing a two-goal margin in the second.
"I didn't have much to shoot at, but I was able to put it in the corner," Alfredsson said.
Toskala, who struggled in the preseason after leaving San Jose as a free agent, stopped 26 shots in his Toronto debut. The Finnish goalie acknowledged that Alfredsson picked just the right spot on the winner.
"Yeah, right under the bar," Toskala said. "Good scoring chance, good shot."
Dany Heatley assisted on Alfredsson's opening goal 8:18 into the game before he scored on a power play at 13:06 of the second to put Ottawa up 2-0 -- though only once a video review determined his shot had barely crossed the goal line.
"It's a goal and a great save at the same time, if that's possible," Maple Leafs coach Paul Maurice said. "I mean, he got there and it was just a matter of inches on that. And the game-winning goal was a perfect shot by a fantastic player."
Sundin's goal was his 389th with the Maple Leafs, tying Darryl Sittler's franchise record.
Martin Gerber made 41 saves for the Senators.
"You play your big rival and you win both games -- it's a good start," Gerber said.
Alex Steen had an apparent goal waved off midway through the second period that would have tied the game at 1 for the Maple Leafs. Jason Blake drove to the net and collided with Gerber before Steen poked the loose puck under Gerber's pad and into the net at 10:35.
Referee Chris Rooney waved his arms and, after a brief delay, the goal was disallowed.
"I think that Jason did everything he could -- he was up on one foot -- to get out of the way," Maurice said. "It's a judgement call."
Just hours after he signed a six-year, $45-million contract extension, Heatley scored twice -- including the overtime winner -- in Wednesday's 4-3 win at Toronto.
Ottawa's Chris Neil was penalized for diving as Alex Ponikarovsky was sent off for tripping at 15:47, just three seconds after Sundin scored his first of the season at 15:44 of the second to draw the Maple Leafs within 2-1.
Stajan tied it at 2 when he scored a shorthanded goal at 16:16.
- Toskala went 0-3 with a 4.69 goals-against-average and an .854 save-percentage in the preseason after signing a two-year, $8-million contract as a free agent.
- Sundin has 524 career goals, including 135 with the Quebec Nordiques from 1990-94.
- Before the game, the Senators raised a 2007 Eastern Conference Champions banner to the rafters.
- D Wade Belak didn't dress for Toronto.
- D Luke Richardson was Ottawa's only healthy scratch for the second straight game.
- The Senators are 8-4-3 in home openers.