The small Central American nation with a minor World Cup pedigree came from behind to shock 2010 semifinalist Uruguay 3-1. Then Mario Balotelli — who else? — scored the decider for Italy in a 2-1 win over England.
If anything, it showed the value of special players at the World Cup. While Italy thrived with Balotelli on the pitch, Uruguay suffered with Luis Suarez sitting on the bench with a bad knee.
Uruguay was powerless for the last hour of the match against an underdog without marquee players, but with no fear of playing against traditional powers.
"What we take into the next games is confidence," said Costa Rica coach Jorge Luis Pinto.
For a third straight day, the World Cup in Brazil lived up to its samba billing as goals kept pouring in, with Colombia punishing Greece 3-0. The other Group C game between Ivory Coast and Japan was played late so it could be broadcast live Sunday morning in Asia.
The leaden Amazon humidity in Manaus was supposed to stifle play, but Italy and England produced a display of attacking and tactical football.
Wily Andrea Pirlo, at 35, set up the first goal with a deft stepover to give Claudio Marchisio room for a long-range shot. In injury time, when players much younger than him had already come down with cramps, Pirlo sent a swerving free kick that hit bar.
Balotelli undid the equalizer from Daniel Sturridge with a 50th minute header. Earlier, he almost scored from an extreme angle only, getting the ball past goalie Joe Hart only to see Phil Jagielka head it off the line.
After the Netherlands spectacular 5-1 rout of defending champion Spain on Friday, it was another day of football at its best.
Teams from the Americas are 5-1, with victories by Brazil, Chile, Mexico, Costa Rica and Mexico. Uruguay's loss to Costa Rica is the only defeat for a team from this side of the globe.
Even though Costa Rica had looked strong in qualifying, few expected a victory over Uruguay, especially after Edinson Cavani scored the opening penalty.
Costa Rica then conjured up the spirit of 1990, when it upset Sweden and Scotland to reach the second round in its first World Cup.
Striker Joel Campbell tied the game in the 54th and Oscar Duarte scored on a diving header just three minutes later. Substitute Marcos Urena added the third with six minutes left.
"We spotted that they had weaknesses and we looked at those. We worked hard on headers and ways to dominate in the air and we did that tonight," Costa Rica coach Jorge Luis Pinto said.
Diego Forlan won the Golden Ball 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, when all thought the nation would fizzle after its great star Radamel Falcao had to withdraw from the World Cup with an injured knee.
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.
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