The biggest variable in the Group A match between Korea and the Czech Republic at the 2026 FIFA World Cup is altitude adaptation. The Guadalajara Stadium, where the match takes place, sits at an elevation of 1,571 meters above sea level. In addition, heavy rain is forecast at the venue around kickoff time, raising the possibility of a new variable: a match played in wet conditions.
According to FIFA on Wednesday, Korea and the Czech Republic prepared entirely different strategies regarding the high-altitude playing environment.
Korea held a pre-camp from May 18 (Korea time) in Salt Lake City, U.S., which sits at an altitude similar to Guadalajara. The national team moved to its base camp in Guadalajara, Mexico, where the match against the Czech Republic is held, on June 6, and will play after six days of acclimatization training on site. The Czech Republic, by contrast, trained at a base camp in Texas, U.S., before moving to Guadalajara the day before the match.
The difference in how the two teams approach the altitude adaptation issue was also evident at the official press conference held the day before the match. Korea coach Hong Myung-bo appeared at the official press conference held at the Guadalajara Stadium in Zapopan, Mexico, on Tuesday and said, "We are completely adapted overall." He added, "I think the players have a sense of relief and confidence in their hearts that we have adapted to the high altitude." It was an expression of confidence that Korea, which put effort into altitude adaptation, would overwhelm the Czech Republic, which did not. The Czech Republic coach Miroslav Koubek, on the other hand, was confident, saying, "Weather and environment are always discussed topics, but personally I don't mind much." He added, "We have the situation well under control." This means he intends to focus on in-game strategies such as tactics rather than environmental factors like altitude.
Experts pointed out that at high altitude, low oxygen slows physical recovery and the ball travels faster, making adaptation an important competitive factor. Park Ji-sung, a JTBC commentator who played at several high-altitude stadiums during his playing days, including Iran's Azadi Stadium located at 1,300 meters above sea level, emphasized that acclimatization training would bring a clear advantage. "Looking at the results Mexico has achieved at home over the years—as the capital Mexico City is at high altitude—there is clearly some impact on teams that have not adapted to the high-altitude environment," he said. "Korea needs to make good use of that aspect."
The Korean national team, which successfully completed its altitude adaptation, is full of confidence. Son Heung-min (LAFC), who appeared at the press conference alongside coach Hong, said, "The team atmosphere is really good, so much so that you can feel it in the players' eyes." He added, "I think everyone is preparing well in their respective positions." He continued, "Every World Cup match is important enough for a player to stake his life on. In the match against the Czech Republic, we will do more than we have and definitely win." Hong also said, "Twelve years ago at the 2014 Brazil World Cup, we failed (eliminated in the group stage with one draw and two losses), but based on much experience since then, I think we have prepared well for this World Cup." He added, "We have created an atmosphere where the players can play excitedly, enjoyably, and energetically."
A sudden variable—rain—is also expected on site. In the area around Guadalajara Stadium on Wednesday, when the match against the Czech Republic takes place, 2.8 millimeters of rain is forecast at 8 p.m., the kickoff time, and 11.9 millimeters at 9 p.m., when the second half begins. If heavy rain falls as forecast and the match turns into a wet-condition affair, the Czech Republic—which mainly uses long balls and set-piece strategies utilizing tall players—is more likely to take the initiative than Korea, which builds its game through passing.
Han Joon-hee, a Coupang Play commentator, emphasized, "If heavy rain falls and water begins to pool on the pitch, it is absolutely disadvantageous for Korea, which plays a passing game." He added, "Since a difficult match is expected in the second half with heavy rain, there is a need to prepare a strategy that goes for the win in the first half."
Meanwhile, center back resource Kim Tae-hyun (Kashima) injured his ankle in training the previous day, making it difficult for him to play in any of the three group-stage matches. Under FIFA rules, the final roster can be changed until 24 hours before the first match's kickoff, but coach Hong, after much deliberation, chose to keep Kim Tae-hyun with the team rather than calling up a replacement. With Kim Tae-hyun out of the lineup, Korea now bears the burden of playing all three group-stage matches with four center backs: Kim Min-jae (Bayern Munich), Lee Ki-hyuk (Gangwon), Lee Han-beom (Midtjylland), and Cho Wi-je (Jeonbuk). The role of Kim Min-jae, who must lead the "newcomers" such as Lee Ki-hyuk, Lee Han-beom, and Cho Wi-je on his own, has become even more important.
