Mikko Koskinen made 31 saves and is 7-0-0 on home ice this season. Edmonton has won six straight at Rogers Place to improve to 10-4-1 at home.
''You always want to make your own rink a tough building to play in,'' Draisaitl said. ''We have struggled with that a little bit the seasons before that. We have been really good at home of late and hopefully we can keep that going.''
''We weren't playing bad hockey, just a couple of mistakes here and there and it's in the back of the net and you're chasing again,'' captain Claude Giroux said. ''The third period we played great again, but we're just chasing every game.''
Edmonton got on the board with 7 1/2 minutes remaining in the first period when Draisaitl fed the puck in front to Chiasson, who beat goalie Anthony Stolarz for his career-high 14th goal of the season in his 27th game. Chiasson's previous best came in 2013-14 over 79 games with Dallas.
''When you win a Cup, it is a little surprising he didn't have a deal or nothing,'' McDavid said. ''He came in on a PTO and worked hard and earned a job and has been having a great year. I couldn't be happier for him. He is a fun guy to play with. He has a knack for scoring and is finding a way to get open.''
The Oilers added to their lead at exactly the same point in the middle period when McDavid banked a shot from behind the net off Stolarz's rear end for his 18th.
Just more than a minute later it was 3-0 when Larsson scored his first of the season on a shot from the top of the circle following a give-and-go with Ryan Spooner.
The Flyers ended Koskinen's shutout bid midway through the third on a shot by Voracek that initially appeared to carom off Couturier into the net. Koskinen has shutouts in three of his seven home starts this season.
McDavid put the game away with an empty-netter.
NOTES: It was the first of two meetings between the teams this season. The Flyers won both games last season. ... Stolarz got the start with two other goalies unavailable. Michal Neuvirth returned to Philadelphia for the expected birth of his child, and Brian Elliott (lower body) also headed back east for a scheduled medical appointment. ... Oilers D Caleb Jones made his NHL debut. He is the younger brother of Columbus D Seth Jones.
Flyers: Finish a five-game road trip Saturday in Vancouver.
Oilers: Play at Vancouver on Sunday.
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