HERNING, Denmark -- Host Denmark upset Finland 3-2 Wednesday and defending champion Sweden stayed perfect at the ice hockey world championship, shutting out Austria 7-0 for its fourth straight victory.
Olympic runner-up Germany rebounded from three straight losses, handing newcomer South Korea a 6-1 defeat.
Switzerland recovered from a loss to the Czech Republic with a 5-2 victory over Belarus.
Sweden leads Group A in Copenhagen with 12 points. Switzerland and Russia have nine while Austria is on one.
Denmark neutralized the Finnish firepower that scored 23 goals in the previous three games. Denmark's victory was the second against Finland at the world championship.
"They played really well,'' Aho said. "We had enough scoring chances to win this game, but they had a great goaltending and the way they played was hard for us to beat today.''
Finland outshot Denmark 35-17.
After a goalless opening period, Frans Nielsen broke the deadlock, giving the hosts the lead in Herning 2:28 into the second. Aho answered two minutes later but Oliver Bjorkstrand restored the surprise lead again. Captain Mikael Granlund equalized for Finland in the third, but Nichlas Hardt scored the winner with 1:59 left. Finland pulled goalkeeper Ville Husso but Denmark held firm.
"No matter how the tournament is going to finish, [this victory] will always be in my memory,'' Nielsen said.
Finland still leads Group B with nine points after four games, the United States is a point behind and Canada trails by another point. Both the U.S. and Canada have a game in hand.
Denmark and Germany have five points.
Yasin Ehliz scored twice for Germany and Leon Draisaitl, Patrick Hager, Frederik Tiffels and Yannic Seidenberg added one apiece in Herning.
"We got a lucky bounce to go up one-zero and we played relatively solid hockey going from there," German captain Dennis Seidenberg said. "Hopefully, we can build on that."
Brock Radunske scored for South Korea at 6-0, only the second goal for the Koreans at the tournament.
"If we can get a couple guys score, that's kind of [a] snowball, picks up the confidence for everybody on the team," Radunske said. "Next games are not gonna get any easier; it's top countries, top players in the world. We just have to use it as a learning experience."
Radunske said South Korea, which has lost all four games so far, wants to show in the rest of the tournament that "we deserve to be in this division."
After losing its first three games, Belarus replaced coach Dave Lewis with assistant coach Sergei Pushkov, but that change has yet to boost Belarus.