For a second day running, this spectacular World Cup left everyone in awe. This time, it was Costa Rica which produced a huge upset.
A day after defending champion Spain was sensationally routed 5-1 by the Netherlands, a small Central American nation with a minor World Cup pedigree came from behind to beat 2010 semifinalist Uruguay 3-1.
Costa Rica's victory spoilt a perfect record so far for South American teams, with Colombia having beaten Greece 3-0 in Saturday's opener following victories for Brazil and Chile over the previous two days.
It also proved that while Colombia can thrive without its injured star Radamel Falcao, Uruguay is lost without its top striker Luis Suarez, who was sitting on the bench nursing a bad knee. Adding insult to injury, Maxi Pereira became the first player to be sent off at the 2014 tournament after he kicked Costa Rica's best player, Joel Campbell, to the ground in the closing minutes.
The result left Costa Rica top in a Group D featuring of three former champions, albeit with Italy and England playing later.
In a free-scoring tournament, the goals continued to flow on Saturday, following the trend set by the Netherlands. And like Spain, Uruguay proved that four years can make all the difference at the World Cup.
Along with goals, a World Cup also thrives on upsets. And even though Costa Rica had already proven in qualifying it was a solid team, few would have counted on Uruguay to fold so quickly after Edinson Cavani scored the opening goal.
Costa Rica conjured up the spirit of 1990, when it upset Sweden and Scotland to reach the second round in its first World Cup. The 2014 team fought back and victory did not come against the run of play.
Diego Forlan won the Golden Ball title as best player four years ago, but at 35, he was a shadow of his former self and was replaced as Uruguay went looking for a way back into the game. But no one could step up to take over from the injured Suarez.
Compare that to Colombia, which showed off its new generation to the world.
With Falcao in the stands, Colombians were cheering 22-year-old playmaker James Rodriguez, handily called "El Nuevo Pibe," or the "New Kid." Rodriguez led his team and scored Colombia's third goal, sealing his nation's first World Cup victory in 16 years.
World Cup Group D: Uruguay vs Costa