It has been 32 years since the USA last hosted the World Cup in 1994. Back on home soil at Los Angeles Stadium in Inglewood, it took just seven minutes for the team to score their first goal - but it was not by their own doing.
American striker Christian Pulisic managed to evade two opponents before shooting the ball - which deflected off Paraguay's Damian Bobadilla and into his own net.
The first unassisted goal was scored by USA's Folarin Balogun in the 31st minute, shortly after the country had an earlier goal disallowed.
At that point, Paraguay seemed to give up, while the USA continued to create more chances. Just before the end of the first half, they struck for the third time - again with Balogun as the scorer.
"It felt great that the half ended the way it did and that the fans were so excited by the effort," said Christian Pulisic.
For Paraguay, it has been 16 years since the country last qualified for the World Cup. But it may not have been the comeback they had hoped for.
But the match wasn't over. Just before the final whistle, USA's Giovanni Reyna scored the team's fourth goal in the eighth minute of added time.
The USA will face Australia in their next match, while Paraguay will face Turkey.
