Uruguay found out. So did Italy.Â Now itâ€™s Germanyâ€™s turn.
A succession of other strong teams almost found out, including Brazil, Argentina and the Netherlands.
They found out -- some in the cruelest way possible -- that there are no longer any certain wins in World Cup play. In fact, there are few easy wins.
Germany, a World Cup favourite, survived a battle royale Saturday against Ghana, emerging 2-2 in a game that probably produced the tournamentâ€™s best half of soccer to date.
It was not the type of game anyone expected.
Ghana lost their first game to the United States while Germany demolished Portugal.
What was expected was a German victory that would give them control of the group. As has happened so often in this World Cup, the expected never occurred.
Costa Rica stunned both Uruguay and Italy. Mexico gave Brazil a wicked battle. The Netherlands had their hands full with Australia.
Also on Saturday, it was only a magic moment from Lionel Messi in the 91st minute against Iran that prevented Argentina from embarrassment.
Some of those underdog teams are better than others, but it doesnâ€™t matter -- the results were surprising.
Ghana-Germany offered up more of the same.
The first half was pedestrian.
The second half exploded like an M-80 firecracker. It didnâ€™t stop with one explosion. It was run for cover time as the Black Stars and Die Mannschaft took turns torching each other to the delight of anyone watching.
Germany took the lead with Mario Gotze. Andre Ayew came right back for Ghana before Asamoah Gyan gave the Black Stars the lead.
Minutes after coming onto the pitch, Miroslav Klose knotted it for Germany. The goal tied him with Brazilâ€™s Ronaldo for the most goals in World Cup history.
There were no more goals but more than enough thrilling moments to make the fillings in your teeth shiver.
The tournament is approaching its midway point and the quality of soccer thus far has not quenched anyoneâ€™s thirst for world class soccer. Instead, it has created an unquenchable thirst to see more of this spectacle.
The idea that nations such as Iran, Costa Rica and even Ghana can demand the very best of historically dominant teams and emerge with more than just their pride, is riveting stuff.
Iran and Argentina played earlier on Saturday and, while the Albiceleste were not on form, that was almost secondary to the drama of a true soccer minnow standing up to a true soccer power.
Iran deserved a point. There was a certain disappointment among neutrals when Messi ended the contest in added-on time.
The only redeeming factor to the undeserved end was the quality of Messiâ€™s goal. It spoke more to Messiâ€™s true greatness rather than any weakness on the part of Iranians.
The goal supplemented the enchantment of a game.
Here was an Iranian team made up of players who are virtually unknown to most soccer people, only being beaten by a goal conjured up by a soccer shaman.
Ghana was able to come back from a late calamity against the United States in its opening game, enriching yet another World Cup.
In 2010, the Black Stars hearts were broken by the ultimate theft.
With a chance to make it to the semifinals in South Africa -- the furthest an African nation would have advanced -- Uruguayâ€™s Luis Suarez deliberately handled the ball to prevent it from going into the net. The subsequent dramatics included a missed penalty and a loss on kicks from the penalty spot.
After Ghana gave up a winner in the 86th minute to the Americans, it wouldnâ€™t have been surprising if they simply felt the fates were against them.
When Ghana went down early in the second half to the Germans on Saturday, the odds of finding the reserves needed were indeed long.
But this is Brazil 2014, where anything is possible.
Ghana was just the latest team to prove that.
It wonâ€™t be the last team to do so.