Nylander won the opening face-off, took a pass from Auston Matthews, and drew a hooking penalty on Duncan Keith while going in on a breakaway. He went forehand to backhand to beat goalie Jeff Glass past his blocker on the penalty shot.
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"I think we just saw they lined up three across the red line, so we were able to get some offense right off the bat off the face-off," Nylander said. "I think that was one of the main factors of us getting the penalty shot. I just thought I needed to throw a little harder fake on him so he'd bite on that one. I went on the backhand in the two previous breakaways I had, I don't know actually why I went to the backhand, but third time's the lucky charm."
Mitchell Marner and Nazem Kadri scored for the Maple Leafs (27-18-5), who won for the second time in seven games (2-2-3).
"They were fast, we were slow in the first," Toronto coach Mike Babcock said. "They skated us into the ground, and it looked like [Jonathan] Toews and [Patrick] Kane still thought they should be the best players and we were just learning how to play. And then I thought we dug in and got playing better and, obviously, a big win for our hockey club. I don't think it was pretty, but we found a way to get it done."
Brent Seabrook scored, and Nick Schmaltz had a goal and an assist for the Blackhawks (22-19-7), who lost their fourth straight game (0-3-1).
"A lot better tonight, but obviously we want two points," Schmaltz said. "Came out with one. Gotta regroup and get ready for tomorrow (against the Detroit Red Wings)."