UFA, Russia — Miro Aaltonen scored twice and added an assist before leaving the game with a serious ankle injury Wednesday as Finland defeated Latvia 5-1 at the world junior hockey championship.

Rasmus Ristolainen added a goal and an assist for the Finns (1-0), while Artturi Lehkonen and Markus Granlund also scored. Joel Armia chipped in with two assists.

Joonas Korpisalo made 11 saves to get the win in Pool A.

Aaltonen had to leave the game after a third-period collision with a Latvian player.

“His tournament is over because his ankle is very bad,” said Finnish coach Harri Rindell, adding the 19-year-old forward may require surgery. “He was so depressed because he really wanted to play and he is in great shape. That’s hockey, unfortunately.”

Nikolajs Jelisejevs had the only goal for Latvia (0-1), which got 39 saves from Elvis Merzlikins.

Sweden 4, Czech Republic 1

Joel Lassinantti made 25 saves Wednesday as defending-champion Sweden opened the world junior hockey championship with a 4-1 win over the Czech Republic.

Sebastian Collberg, Elias Lindholm, Filip Sandberg and Filip Forsberg scored for Sweden (1-0), while Mikael Vikstrand added two assists.

Lukas Sedlak had the only goal for the Czech Republic (0-1) while Matej Machovsky stopped 37 shots.

“I liked the way we competed,” Swedish coach Roger Ronnberg said. “I liked our PK, the way we were blocking shots, and the way we played without the puck, how we came back on the backcheck. It was good. Offensively, we can for sure still play better.”

Pool A action continues for both teams Friday when the Czechs take on Finland (1-0) and the Swedes meet Switzerland (0-0).