The Koreans, ranked 21st in the world, took a surprise 1-0 lead over the sixth-ranked Czechs in the first period. Cho Min-ho took a feed in the slot from Brock Radunske, one of six Canadians on the team, and fired a wrist shot past Czech goalkeeper Pavel Francouz.
The goal sent the near-capacity crowd at the Gangneung Hockey Centre into delirium.
While it took the unified Korean women's team nearly 150 minutes of playing time to notch their first goal, which came on Wednesday against Japan, the South Korean men accomplished the same feat in 7 minutes and 34 seconds.
"This was huge," said Korean coach Jim Paek, the first Korean-born player in the NHL and a Stanley Cup winner. "First night in the Olympics. First game ever in the Olympics. First goal scored in the Olympics. It was a fantastic night for sure."
The lead would not last, though. The Czechs, including several ex-NHL players and 15 who play in Russia's Kontinental Hockey League, levelled about four minutes later when Jan Kovar tapped in a pass from Michal Repik, beating South Korean goaltender Matt Dalton to the glove side.
They took the lead on a short-handed goal. Repik, who played 72 games over four seasons with the NHL's Florida Panthers, intercepted a puck as the Koreans were trying to break out of their zone and charged the goal.
Dalton stopped his first shot, but the puck trickled behind him and Repik whacked it into the net.
"I'd like to have that second one back," Dalton said. "I felt better as the game went on. At the end of the day, I was just trying to give the guys a chance to win the game."
Dalton made 38 saves to keep it close for his team, and the crowd provided a big lift, roaring every time a Korean player carried the puck across center ice into the Czech zone.
"It was tough, they played a really good game," Czech captain Martin Erat said of the Koreans. "A lot of energy and the crowd was behind them so it was a great game for them."
Unlike the unified Korean women's squad, which includes 12 players from North Korea, the South Korean men's team is not integrated and has so far escaped the spotlight cast upon the women.
The men's Olympic tournament is being played without NHL players for the first time since the 1994 Games in Norway's Lillehammer, after the league and the International Olympic Committee failed to agree on covering players' travel and insurance costs.
(Reporting by Dan Burns, editing by Ed Osmond and Toby Davis)
