A clubless Cristiano Ronaldo goes into the championship against the "gold favorite" Ghana.
Here's all you need to know for today's football World Cup games.
Switzerland-Cameroon Group G
When: 11.00 a.m.
Where: al-Janoub Stadium, al-Wakrah
TV: SVT1/SVT Play
- Goes in Milla's footsteps?
Cameroon charmed the football world in the World Cup in 1990. Much thanks to Roger Milla, the then 38-year-old veteran who made four goal when the country reached the quarter final.
In Qatar, "the untamable lions" hope for another experienced attacker. Eric Maxim Choupo-Moting, 33, has been scorching at the end of the club team Bayern Munich, and also became the goal scorer in the World Cup genre against Panama.
- Meet the country of birth
The World Cup opener will be particularly special for Switzerland's Breel Embolo. The striker was born in Cameroon and moved to Switzerland with his mother when he was six years old. However, most of the family still lives in Cameroon.
"It will be a very emotional match for my family", says Embolo according to Blick.
- The goalkeeper receives green light
In the end, it has been uncertain whether Yann Sommer comes to play against Cameroon. The goalkeeper has been injured and played none of Borussia Mönchengladbach's last six league games before the World Cup break.
But the other day, Switzerland's medical team gave the 33-year-old green light to play in the premiere, reports national media.
Uruguay-South Korea, Group H
When: 2 p.m.
Where: Education City Stadium, al-Rayyan
TV/radio: SVT1/SVT Play/P4 Sports-Radio
- The attacking star is ready to play
South Korea's hope rests on the shoulders of Son Heung-Min. However, there have been major questions for the Tottenham attacker after the facial fracture he contracted a few weeks ago.
But now it is clear that Son is coming to play in the World Cup premiere, which confirms the Federal Commander Paulo Bento at a press conference.
- New on the bench
Óscar Tabárez has been a standing feature on Uruguay's bench in the World Cup context. The trainer has led the national team in four World Cup finals (1990, 2010, 2014 and 2018), but was fired a year ago after the weak start of qualification.
In Qatar, it will instead be the World Cup debut for 47-year-old Diego Alonso, who replaced Tabárez last year.
- Routine Uruguay
If the captain lacks World Cup experience, the same cannot be said of the players. Uruguay have travelled to Qatar with an experienced team. The squad includes five players - Luis Suárez, Edinson Cavani, Diego Godín, Martín Cáceres and Fernando Muslera - who have played in the last three World Cup finals.
Portugal-Ghana Group H
Where: Stadium 974, Doha
TV/radio: TV4/C More/P4 Sports-Radio
- Clubless Ronaldo ready
Portugal's World Cup preparations have been mainly about Cristiano Ronaldo. On Tuesday it was clear that Manchester United is breaking the contract with the superstar after an attentive television interview, where Ronaldo sawed the club, the owners and the coach.
Ronaldo believes, however, that the controversy will not adversely affect him in the World Cup.
"We've had good trainings, both the team and myself, I'm ready to start the World Cup in the best possible way", he says at a press conference.
- President on site
Portuguese President Marcelo Rebelo de Sousa will be in Qatar for the World Cup. But not just to support the national team.
The President will also raise other issues during his stay.
"I will be involved in a debate on education, and one of the basic elements of education is human rights. Therefore, I will discuss human rights in Qatar the day after tomorrow (read: Thursday), according to the Portuguese media."
- Confident national team captain
Ghana is not one of the favorites of bringing home the World Cup trophy in Qatar.
But the quarter-finals from the 2010 World Cup will be surpassed, which is what the Federal Commander Otto Addo thinks.
"Our goal is to reach the finals", he says in an interview with Spanish As, and then gets the question which team he thinks is the favorite to win the World Cup:
"Ghana, Addo replies, adding that he is serious."
Brazil – Serbia Group G
Where: Lusail Stadium, Lusail
TV/radio: TV4/C More/P4 Sports-Radio
- World Cup Hero Supports Neymar
Neymar is one of the biggest stars in the World Cup. However, the Brazilian attacker has suffered a lot of criticism over the years for things that happened alongside the plan.
However, not everyone has an evil eye for the fix star.
"It's cool, do what you're supposed to do on the field and try to forget everything else, all the sounds coming from outside," writes Romário, Brazilian World Cup hero in 1994, on the site The Player's Tribune.
- Altitude duels in focus
In order for Brazil to get a good start on the World Cup, it is necessary to manage the game in the air. The TV channel Globo notes that Serbia has the World Cup's most large team, with an average length of 187.1 centimeters, to compare with Brazil's 180.7.
"We will do everything we can to neutralize their forces", says Brazilian attacker Richarlison at a press conference.
- Serbia signposts
Since the break-up of Yugoslavia, Serbia has never been able to move on from a World Cup group game.
The Federal Commander Dragan Stojkovic, on the other hand, has it as a midfielder in the Yugoslav national team that reached the quarter final in the World Cup in 1990.
"With his experience, he can show us how to succeed in this championship", says attacker Aleksandar Mitrovic according to international media.