Van Riemsdyk put the game out of reach at 5-1 with his team-leading eighth of the season on a shot that squeaked past Boucher just 71 seconds into the third. McGinn then scored a goal for Philadelphia with 32 seconds left in regulation.
Coming off a 3-0-0 road trip, which included a 6-0 victory in Montreal on Saturday night, the Leafs came out with a slow first shift Monday.
Philadelphia worked the puck into the Toronto end and kept it there until Simmonds banged the rebound of a Luke Schenn shot home just 38 seconds into the game.
Philadelphia carried the play against the Leafs for much of the rest of the first until Mikhail Grabovski, who was cleared earlier in the day of any wrongdoing in an alleged biting incident against Montreal on Saturday, hit both posts behind Bryzgalov only to see the puck stay out.
That chance seemed to spark the Leafs and Phaneuf tied the game at 14:49 with a one-timer off a pass from Leo Komarov that beat a screened Bryzgalov.
"We didn't start that well. When you get scored on the first shift of the hockey game ... but I think we were fortunate to get out of the first period tied 1-1 and that's what our message was to our players," Carlyle said. "The expectations for our group are to play a lot higher level than what we did."
Notes: Schenn played 310 games in four seasons with the Leafs before being traded to Philadelphia in June for van Riemsdyk. The deal was viewed as a fresh start for both former top-five draft picks and reunited Schenn with his brother Brayden. Schenn, who wears No. 22 with Philadelphia, started for the Flyers on defense and got a small applause from the crowd about 10 minutes before the opening faceoff. The Leafs honored Schenn midway through the first period for his work supporting the Canadian military. ... Nazem Kadri also had two assists for Toronto. ... The Leafs are 6-1-0 on the road this season. ... Both teams had a rough night on the power play. Toronto was 0 for 3, while Philadelphia was 0 for 5. ... Philadelphia was coming off a 3-0-1 homestand. Monday's game was the first of a six-game road trip that will also see the Flyers travel to Winnipeg, New Jersey, Montreal, Long Island and Pittsburgh. Philadelphia is 1-6-0 away from home.