They're hoping to get their skip his first world title at this year's tournament in Halifax.
Pat Simmons will guide the host Canadian side at the competition, which begins Saturday at the Scotiabank Centre. He took over skipping duties from Morris after the team struggled in the early going at the recent Tim Hortons Brier.
Simmons went on to lead the Calgary rink to the playoffs and a successful title defence as the first Team Canada entry at the national championship. A 6-5 victory over Northern Ontario's Brad Jacobs gave them a berth in the 12-team world championship along with a chance to make up for a disappointing fourth-place finish last year in Beijing.
"That's one of our big motivators going into Halifax," said Morris. "We want to get that world championship for Pat."
Simmons, Rycroft and Thiessen won the Brier last year with Alberta skip Kevin Koe. However, reports surfaced shortly before the 2014 world championship that Koe planned to move forward with a new lineup for this season.
They still made it to the bronze-medal game but settled for fourth place after a loss to Switzerland. It was the first time since 2001 that Canada had missed the podium at the world playdowns.
Koe's former teammates later recruited Morris as skip and had an automatic entry at the Brier as the defending champions. Team Canada played a light schedule ahead of the national playdowns and stumbled to a 2-3 record after five games.
That's when Morris demoted himself to third and handed skipping duties to Simmons, who shone in the role. They made the final four, pulled off two close playoff wins and knocked off the reigning Olympic champions in a nailbiting final.
Not bad for someone who hadn't been a full-time skip in five years.
"As it turned out, it came back relatively quick," Simmons said in a recent interview. "There's still probably room for improvement in that respect, but I definitely was pleased with how quickly everything did come back for sure."
Simmons, a Moose Jaw native, skipped the Saskatchewan entry at the Brier for several years before starting to move away from skip duties in 2010-'11. He joined skip Steve Laycock's team that season, although Simmons still threw last stones.
Simmons moved to Koe's team the following season and spent three years as a third for that rink.
Morris, meanwhile, won a world championship in 2008 in Grand Forks, N.D., with Marc Kennedy, Ben Hebert and retired skip Kevin Martin, a team that won Olympic gold at the 2010 Vancouver Games. Rycroft and Thiessen won a world title with Koe and Blake MacDonald in 2010 at Cortina d'Ampezzo, Italy.
Koe added Kennedy, Hebert and Brent Laing to his team this season. They won the Alberta provincials but didn't reach the Brier playoffs.
Morris appeared much more comfortable as a third at the Brier, a position he played for Martin from 2006 to 2013. He said he feels "100 per cent confident" that his team can win the world championship, adding everyone feels really natural and comfortable in their positions.
Thomas Sallows will serve as the Canadian alternate and Earle Morris is team coach. Round-robin play begins Saturday and Canada will open against John Shuster of the United States in the evening draw.
Norway's Thomas Ulsrud is back to defend his title. He beat Sweden's Oskar Eriksson 8-3 in last year's championship game.
Sochi Games bronze medallist and 2013 world champion Niklas Edin will skip the Swedish side while three-time Olympian Ewan MacDonald will guide the Scottish entry.
Norway's Jiri Snitil and China's Jialiang Zang will both be making their seventh career appearance at the world championship. Italy will be skipped by Joel Retornaz, although he'll throw third stones ahead of teammate Amos Mosaner.
Other skips include Switzerland's Marc Pfister, Russia's Evgeny Arkhipov, Japan's Yusuke Morozumi and Finland's Aku Kauste. Round-robin play continues through April 2 and the medal games are set for April 5.
Canada has won gold on 34 occasions since the event was first held in 1959. The most recent Canadian title came in 2012 when Glenn Howard won in Basel, Switzerland.
— With files from Canadian Press sports reporter Donna Spencer.
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