Fellow teammates Carter Rycroft and John Morris were stunned too.
It was gold or bust for the Canadians at the world men's curling championship. The way they played Saturday night, they'll be hard-pressed to make the podium at all.
Sweden's Niklas Edin was dominant in a 6-3 semifinal victory over Canada at Scotiabank Centre. With the win, he advanced to Sunday's gold-medal game against defending champion Thomas Ulsrud of Norway.
Canada will have to settle for an appearance in the bronze-medal game against Finland's Aku Kauste.
"To come up with a stinker in the semifinal is never a lot of fun," Morris said.
Simmons had the worst shooting percentage of the eight curlers at just 72 per cent. That didn't cut it against the 2013 world champion, who was a perfect 100 per cent on the night.
Sweden shot at an impressive 92 per cent as a team, well ahead of Canada at 77 per cent.
"I don't think it was possible to play any better than that," Edin said. "It's for sure the best performance we have done as a team so far."
The Canadian errors were frequent and Sweden made the host team pay.
Simmons drew gasps from the partisan crowd when he flashed his final throw in the first end to give Sweden a steal of one. He was also heavy with his first rock in the second end before recovering to score a single.
Edin scored deuces in the third and fifth ends for a 5-2 lead and added a single in the sixth. Simmons got one back with a draw in the eighth, but lost the hammer.
The Swedish skip used it for a double takeout and a blank in the ninth to retain last rock. He ran Simmons out of stones in the 10th end.
"This is as tough as they get," Simmons said of the defeat. "It's not what we came here to do is to play for the bronze."
Ulsrud had the day off Saturday after topping Simmons in the Page playoff 1-2 game on Friday night. Canada and Norway shared the best round-robin record at 10-1.
Edin beat Kauste 7-4 in the Page playoff 3-4 game to reach the semifinal.
Simmons, Thiessen, Rycroft and former skip Kevin Koe finished fourth at last year's world championship in Beijing. John Morris joined the team as skip this season before switching to third midway through the Tim Hortons Brier.
The move paid off as they made the playoffs and came through with three big wins for the national title. However, the Canadians had trouble with the big guns this week, falling in a rout to Ulsrud during the round robin and again in a tight 1-2 game.
In Canada's first must-win game, it was Edin who delivered the knockout blow.
"Without a doubt that was our worst game together this year," said Canada coach Earle Morris.
Simmons and his teammates must now focus on trying to bounce back in the third-place game. Kauste, meanwhile, will have no trouble getting up for it.
The Finnish skip was not expected to make the final four in the 12-team field. He finished the round robin at 6-5 and came through with a tiebreaker win over the United States to get the fourth seed.
"We have one more game and we surely want to win a medal, it would mean a lot for us," Kauste said. "I don't know about the other playoff teams. They are all world champions so they probably don't care about any other medals than the gold, but bronze would be really big for us."
Attendance was 2,839 for the 3-4 game and 3,705 for the semifinal. The venue's capacity for curling is 10,500.
Canada hasn't won gold at this event since Glenn Howard took the 2012 title in Basel. The Swiss city will host the tournament next year.
Morris won a world championship in 2008 in Grand Forks, N.D., with Marc Kennedy, Ben Hebert and retired skip Kevin Martin, a team that also 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.
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