Konecny's third-period goal earned Canada a 3-2 quarter-final victory over Switzerland on Thursday. He scored with 30 seconds remaining in regulation after Switzerland had tied it earlier in the period.
Switzerland pulled goalie Gauthier Descloux for the extra attacker afterwards but couldn't beat Canadian netminder Mason McDonald to force overtime.
"I think it's the same old story, we're finding a way," Canadian team coach Kevin Dineen said after the game. "But we've got to do a much better job of showing up the way we play.
"Hockey Canada put together some good character players and some talented players. I think we've survived on our talent, now we have to start relying on a little more character."
Canada, which finished the preliminary round atop Group A, faces the Czech Republic in the semifinals Saturday in Lapeenranta, Finland. The Czechs, who were second to the U.S. in Group B, advanced with 3-2 quarter-final win over Russia here.
John Quenneville and Jake Virtanen had the other goals for Canada, the defending tournament champion. McDonald stopped 19 shots.
Dominik Diem and Kevin Fiala replied for Switzerland, which outshot Canada 21-17 but was just 1-for-7 on the man advantage.
"Our penalty kill really stood out and I give a lot of credit to our defence, they had a really solid game," Dineen said. "That group really made a difference for us, it was a really satisfying win from that perspective."
However, Dineen felt his players didn't make things easy for themselves throughout the game.
"Undisciplined penalties, I thought, were an issue for us," he said. "We put ourselves in a lot of disadvantages, not just in terms of manpower but wearing out the body over and over.
"Also, our puck decisions have to be better, both in our defensive zone and at the opponent's blue-line. I think we were just a little bit too cute and it kept on coming back on us."
Diem opened the scoring at 7:50 of the first before Virtanen tied it on the power play at 17:28.
Quenneville, a second cousin to Chicago Blackhawks head coach Joel Quenneville, had the lone goal of the second, putting Canada ahead 2-1 with an even-strength marker at 11:58.
But the Swiss tied it again on Fiala's power-play goal at 15:43 of the third, setting the stage for Konecny's late-period heroics.
"We got the right guys on the ice and fortunately ended up with the puck," Dineen said "Even though it wasn't overtime it was pretty dramatic nonetheless.
"I thought the Swiss played a heck of a game, they were the better team for stretches. We might've learned a pretty good lesson and survived this one. We're not going to be that fortunate against the Czechs. We're going to have to change the way we do our business to have that success."
Dineen saw some of the Czech Republic-Russia game and was impressed with the Czechs' resilience.
"I thought in all honesty the Russians played very well but obviously they (Czechs) are a worthy opponent and found a way to stick around," Dineen said. "They're pesky and at the end of the night ended up with the win."
The Americans take on Sweden in the other semifinal Saturday. The U.S. beat Slovakia 6-2 in its quarter-final game while the Swedes advanced with a lopsided 10-0 victory over Finland.
The semifinal victors will meet Sunday in the tournament final after the losers square off in the bronze medal game.