The ultimate winner of the World Cup usually comes from one of a handful of elite teams with a long history of success, yet each tournament inevitably features a few early upsets that no one could have predicted.
While many of the usual suspects look to be in a ruthless mood again, past experience tells us that the experts will be shaking their heads at some of the outcomes in the opening group stage over the coming weeks.
Here, we take a look at some games in which the upset radar could start flickering to life, causing some nervous moments for traditional powers.
Switzerland vs. Brazil
When: June 17
Brazil hasn’t lost a group game at the World Cup for 20 years and hasn’t come particularly close to it, either. But Switzerland won nine in a row to begin its qualifying campaign and survived a European playoff. The Swiss upset a seemingly unbeatable team by knocking off Spain in 2010. It will go in as a massive underdog, but might have more of a chance than the oddsmakers suggest.
Tunisia vs. England
When: June 18
The English public celebrated the outcome of the draw in December, and confidently expects easy passage to the knockout rounds. That might be premature, as Tunisia has the smarts to slow the tempo of the game and cause trouble. As England showed in losing to Iceland at Euro 2016, it doesn’t handle pressure, a tight defense and a fiercely determined opponent very well.
Senegal vs. Poland
Where: Otkritie Arena, Moscow
When: June 19
Poland was one of the seven (plus host Russia) seeded teams for the tournament, but hold on a second. It conceded more goals than any other European qualifying group winner and never looked spectacular despite making the quarterfinals of the 2016 Euros. For Senegal, Kalidou Koulibaly is the star of a stout defense, while Liverpool’s Sadio Mane has the ability to break down any team.
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Sweden vs. Germany
When: June 23
The perception that Germany never slips up during the group stage is fair and the reigning champion won its first game of the tournament the last four times, scoring 20 goals in the process. The second game sometimes brings wobbles though, a draw with Ghana last time and defeat to Serbia in 2010. Sweden is resilient, beating Italy in a playoff to qualify, and Bundesliga star Emil Forsberg will have a point to prove.
Nigeria vs. Argentina
Where: St. Petersburg
When: June 26
Nigeria is arguably the strongest of the African teams and has the physicality to match up against anyone. The Super Eagles faced Argentina four years ago and narrowly went down 3-2, but qualified for the last 16 anyway. A recent friendly, albeit without some of Argentina’s top stars, went comprehensively Nigeria’s way. If Argentina already has a top two spot in the group wrapped up by the time they meet, the prospect of an upset is even more likely.
Follow Martin Rogers on Twitter @RogersJourno