Pettersson, 19, was selected by the Flyers in the seventh round (No. 198) of the 2014 NHL Draft.
The 5-foot-9, 187-pound defenseman played the past two seasons in the Swedish Hockey League with Linkoping, where he played 62 games. Pettersson represented Sweden at the 2014 World Junior Championship, winning a silver medal.
I remember the first time at Wrigley Field all of us had the long johns, the turtlenecks and the extra equipment because we were afraid of being cold. Halfway through the first period everybody's ripping everything off and we just ended up wearing what we would normally wear for a game at the United Center.
— Chicago Blackhawks forward Patrick Sharp on the 2009 Bridgestone NHL Winter Classic