Sweden has won an opening World Cup game for the first time since 1958 and ended its worrying goal drought with a 1-0 victory over South Korea that was a must-win if it wants to progress from a tricky-looking Group F.
After dominating the game but missing a string of chances, Sweden won a 65th-minute penalty when Kim Min-woo brought down Viktor Claesson in the box.
Salvadoran referee Joel Aguilar initially waved the Swedes away, before being called to consult the Video Assistant Referee system.
In the third VAR-awarded penalty of the World Cup, Sweden's 33-year-old captain Andreas Granqvist stepped up to sweep the ball low and left of otherwise impressive goalkeeper Cho Hyun-woo.
That fired up the hordes of yellow-clad Swedish fans, who had been fearful their team would misfire again after failing to score in any of their previous three games.
Sweden had not won an opening game at any World Cup since 1958, when it was runners-up in their best performance to date.
The Asians actually began the game far brighter, pressing and harrying for the first 15 minutes against an initially sluggish-looking Sweden.
But the Scandinavians quickly found their rhythm, coping comfortably with Korea's attacks despite the absence of defender Victor Lindelof through illness.
The Swedes created a string of chances, most falling to Marcus Berg, who had one close-range side-foot shot spectacularly saved by Cho off his knee in the 21st minute.
As expected, both teams' single star players were at the heart of their best moves, the silky Son Heung-min busting a lung to try and drive Korea forward from the left flank, and the pacey Emil Forsberg constantly feeding Sweden's big frontmen.
Although not the most attractive of the World Cup games so far, there was a terrific atmosphere in the 42,300-strong crowd at the blue-and-white Nizhny Novgorod stadium next to a cathedral at the confluence of the Volga and Oka rivers.
Sweden next faces Germany, while Korea takes on in-form Mexico who pulled off a major shock by beating the world champions in their Group F opener. Few will give a chance to Korea, who have now only won one of their last 10 World Cup games.