CALGARY -- Canada's Brendan Bottcher lost to a rookie team and dominated a rival contender Monday at the men's world curling championship in Calgary.

Falling 10-9 to unheralded Jeong Yeong-seok of South Korea after thumping reigning Olympic champion John Shuster of the United States 10-1 added up to a mixed bag of a day for the host team.

Bottcher's record was 5-2 behind Norway's Steffan Walstad and Russian Curling Federation's Sergey Glukhov, who were both 5-1 heading into the evening draw.

South Korea's Jeong and his teammates are playing in their first world championship.

They were outscored 40-13 over five losses to start the event, but outplayed Canada early Monday.

"Everyone comes to play against us. Everyone loves beating Canada," Bottcher said. "That's something we know going in. They made a lot of shots in the first half of the game and they earned their lead. They thoroughly outplayed us.

"I thought we outplayed them in the second half. Wasn't quite enough to win the game. We need to expect teams are going to play good against us regardless of what their record is."

Bottcher, third Darren Moulding, second Brad Thiessen and lead Karrick Martin from Edmonton trailed 8-3 after seven ends.

The Canadians battled their way out of handshake territory scoring four in the eighth and stealing two in the ninth.

Up one point coming home without last-rock advantage, Bottcher's attempted freeze with his final stone stayed in the open.

Jeong made the hit for the deuce and the win to get to a record of 2-5.

"Canada, we've watched online, we've watched videos of the strategies and the postures," Jeong said via an interpreter. "It will be a really good experience for us to actually beat them."

The South Koreans won the pre-game draw to the button to have hammer in the first end. They scored three with it to get the Canadians chasing.

It was Canada with hammer and scoring an early three against the Americans in the morning draw. After Canada stole seven points, Shuster shook hands and conceded after six ends.

Bottcher shot 100 per cent against the U.S., but the Canadian skip wasn't as sharp against South Korea at 75 per cent.

"It's easy when you go out there and shoot 100 per cent," Bottcher said. "It's not easy when you go out there and shoot 75 or 80 per cent.

"I think we're a team that tries to win as many of those games as we can and that will give us our best chance to be in the playoffs."

Italy's Joel Retornaz, Scotland's Bruce Mouat, Switzerland's Peter de Cruz and defending champion Niklas Edin of Sweden were all on Canada's heels with 4-2 records.

Italy edged the Swiss 4-3 in the afternoon draw. Germany's Sixten Totzek picked up a first win and handed the Norwegians their first loss in an 8-6 victory.

Jaap van Dorp of the Netherlands also won his first by beating China's Zou Quiang 10-2.

The top six teams in the field of 14 advance. The top two seeds earn byes to Saturday's semifinals at WinSport's Markin MacPhail Centre.

In Friday's qualification round, third plays sixth and fourth faces fifth. The winners move on to the semifinals.

The gold and bronze-medal games are Sunday.

The top six teams also qualify their countries in men's curling for the 2022 Winter Olympics in Beijing. The rest of the Olympic field will be determined in a December qualifier.

There are no spectators for the world championship in Calgary, which was also the case for the Canadian men's, women's and mixed doubles championship there.

Participants are confined to the arena and their hotel to avoid the spread of the COVID-19 virus.

This report by The Canadian Press was first published April 5, 2021.