Day 4 at the World Cup began much the way Days 1 and 2 ended: with a gorgeous, swerving goal off a free kick. This time, it was Serbian Aleksandar Kolarov's turn to show some wizardry with the ball, whipping it over a wall of Costa Rican defenders and past goalkeeper Keylor Navas midway through the second half to earn a 1-0 win in Samara.

The match got testy later — referees had to separate some of the players and coaches in front of the Costa Rican bench — and understandably so: The result put the Serbs in good position in a group featuring three teams who figured to be fighting for second place behind Brazil. 

The action returned to Moscow in the afternoon, and that's when the World Cup got its biggest upset so far: Mexico knocked off defending champion Germany 1-0 thanks to Hirving Lozano's first-half strike from 14 yards out. The match was full of chances for both sides, with Germany firing 25 shots, nine of them on target but none finding the net, leaving goalkeeper Manuel Neuer, midfielder Thomas Mueller and the others to rue the opportunities lost. 

The night's final match brought another surprise result, with Switzerland staving off that stacked Brazil side to manage a valuable 1-1 draw in Rostov-on-Don. After a Swiss clearance fell to his feet, Philippe Coutinho unleased a curling, 20-yard shot that banged in off the far post to give the heavily favored Brazilians the lead 20 minutes in. But Steven Zuber leveled things 5 minutes after the break, using a slight push to create space for a simple header off a corner kick, and the Swiss held on from there.

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