But the Arizona Coyotes goaltender wouldn't take full credit for the victory.
Smith, who's been stellar all tournament, made 23 saves to hold down a fired-up Czech squad and propel Canada into Sunday's gold-medal game against Russia.
"I think we played a solid game and that's most important," Smith said. "We were in a tight hockey game all the way through and we handled it very well."
The home team showed great jump early in the game — inspired by its loud, partisan crowd of supporters.
"Smitty was unbelievable," said Canadian defenceman Tyson Barrie. "The Czechs came out firing the first 10 minutes there. He kinda kept us in it.
"He's been doing that all tournament though. He's been outstanding and we're lucky to have him back there."
Smith has given up just 11 goals through the first nine games of the tournament and has recorded a .931 save percentage — third best behind Connor Hellebuyck of the United States and Sebastian Dahm of Denmark.
In Saturday's later semifinal, Russia beat the United States 4-0 to advance to the gold-medal game. The U.S. will play the Czech Republic, also on Sunday, for bronze.
Taylor Hall opened the scoring for Canada at the 8:40 mark of the first period, converting a slick feed from his Edmonton Oilers teammate Jordan Eberle past helpless Czech netminder Ondrej Pavelec.
"I just kind of beat my guy and Sid (Sidney Crosby) made a great play to me for a breakaway," said Eberle. "I knew I had a guy on my hip and I knew Hallzy was behind me. I thought if I moved it to my forehand, Pavelec would follow me and I'd leave Hallzy with an empty-net. It worked out, so it's good."
Jason Spezza increased Canada's lead to 2-0 at 9:02 of the second period on a sharp-angle shot that snuck inside the far post.
Spezza leads the tournament with 14 points through nine games, while Hall and Eberle are now tied for second place with 12 points each.
"I thought today was probably our best game as a line," said Hall. "We're starting to really read off each other. Sid's such a fast player and he makes plays at high speed so he forces his linemates to kind of play at that level. I think we're starting to work it."
With 1:34 remaining in the second period, Michal Jordan put the first puck of the day past Smith. The crowd's euphoria was short-lived, however, as the goal was immediately waved off because Petr Koukal was in the goal crease.
"I don't even know. honestly," Smith said when asked if there had been interference. "The ref called it. I felt like someone was close, but I was more concentrating on the puck than the guy."
Newly arrived in Prague after his Montreal Canadiens were eliminated from the Stanley Cup playoffs, Tomas Plekanec added an early spark to the Czech attack but was unable to put a puck past Smith. Czech icon Jaromir Jagr was neutralized by Canada's strong team defence, one game after his stellar performance against Finland in the quarter-final.
Sunday will mark Canada's first chance to compete for a world championship medal since winning silver in a 2-1 loss to Russia in 2009.
"This is what you play to get there but there's still one more game ahead of us," said Eberle. "We've got to regroup here, get some rest, probably watch the game and see who we play."
The Russia-U.S. semi was scoreless until more than seven minutes into the final frame, when Sergei Mozyakin wristed a shot over goaltender Connor Hellebuyck.
Alex Ovechkin, making his first appearance in the tournament following the end of his NHL playoffs run, found space in between the goalie's pads three minutes later.
Vadim Schipachyov made it 3-0, and Evgeni Malkin finished it off with 1:25 to go into an empty net. Russia will seek its third title in four years.
"The Russians, of course, are Russians. They've been tremendously skilled and talented," said Canada coach Todd McLellan.
"They can score. They've got a team of players that have played together in the past and they're dangerous the whole 60 minutes."