Alexander Nylander scored twice and 16-year-old Rasmus Dahlin had a goal and an assist as Sweden routed Denmark 6-1 in the opening game of the world junior hockey championship on Monday afternoon.
Carl Grundstrom, Joel Eriksson Ek and Jonathan Dahlen also scored for Sweden, seeking its first world under-20 gold since 2012 in Calgary and Edmonton.
Dahlin, a defenceman in Sweden's top league, is seen as a potential first overall NHL draft pick in 2018 and has been compared to Ottawa Senators star Erik Karlsson. He was used sparingly by coach Tomas Monten until getting regular ice time in the third period, but managed to make an impression in the one-sided match against last year's quarter-finalists.
Nikolaj Krag scored with 2:07 remaining for Denmark on a screened shot from the left circle to spoil Felix Sandstrom's shutout bid.
The Swedes outshot Denmark 33-22.
The Danes led 7-2 in shots through nine minutes but Sweden's attempts came on breakaways by Grundstrom and Tim Soderlund, both stopped by Lasse Petersen.
Nylander, drafted eighth overall by Buffalo in June, showed his class as he picked up a puck from Filip Ahl, made a move in the slot and slid it past Petersen at 210:11.
Monten used Dahlin sparingly in the first, but put him on with the first line near the end and it produced his first point of the tournament. Ahl and Eriksson Ek won a puck battle and got it to Calgary Flames prospect Olivier Kylington, who slipped it across to Dalhlin on the right point for a wrist shot. The rebound went to Eriksson Ek to shoot into an open side at 18:24.
Toronto prospect Grundstrom cruised into the Danish zone, cut across the slot and fed Dahlin at the side of the net 4:30 into the second frame. Grandstrom stole the puck from Oliver Larsen during a Denmark power play and went in alone to score shorthanded at 6:26.
Dahlin took a pass from Gabriel Carlsson, avoided a check and threaded a high wrist shot through traffic and under the crossbar at 13:12.
Nylander redirected a David Bernhardt shot out of the air at 18:22.
The Danes are back in action Tuesday against Finland while Sweden next plays Wednesday against Switzerland.