Damián Bobadilla's seventh-minute own goal put the hosts ahead, before Folarin Balogun struck twice either side of half-time, including a stoppage-time finish to make it 3-0 at the break. Paraguay pulled one back through Maurício early in the second half, but Giovanni Reyna sealed the result with a late fourth in stoppage time. It was the USA's first three-goal World Cup victory since 1930.
Pulisic was substituted at half-time after taking a kick to his calf, with the captain telling reporters afterwards he was hoping it was "nothing" serious. Manager Mauricio Pochettino addressed the situation directly in his post-match press conference.
"He received a kick in his calf and he felt tight at the end of the first half. We didn't want to take any risks. It was difficult for him to walk but hope that it is not a big issue and he can be ready for the next one."
Pochettino was visibly emotional discussing the overall performance.
"So, so proud. Players and staff deserved big credit for this performance. The most important is the performance and the feeling. We know it is only the start and it is nothing. It is only one game. Now we need to be intelligent to keep going in that direction."
He placed the result in the context of hosting the tournament.
"We are so happy because the first game is always so difficult, hosting the World Cup, the expectation but we managed the expectation and pressure. The first 45 minutes were amazing, difficult to find a team to play like this. So happy and so proud."
The atmosphere inside SoFi Stadium, in front of a crowd that included numerous Los Angeles celebrities, drew specific praise from the head coach.
"Amazing. That is what we were waiting for. When you talk about America, that passion, that feeling. Now they realise that soccer in America is massive, it's big."
Captain Tim Ream, speaking to FIFA after the match, reflected on leading the side out for such a significant occasion.
"It's an honour to lead the team and just to be part of the group is a huge honour. We've put in a lot of work and the guys have done a lot to get to this point. To put in a performance like that and get three points and start the way we have is everything that we wanted. Hats off to the guys — a lot of firsts, first goals and first goals, it's been a good night overall."
Ricardo Pepi, who came on as a substitute and was part of the USA's second-half rotation, also spoke to FIFA about the significance of the win.
"It puts us in a good spot, of course. It shows the amount of chemistry we have as a team and we're prepared for the next one and all good vibes here. Being here at home I thought it was a fantastic atmosphere to open up our World Cup."
The result also produced a piece of family history, with Sebastian Berhalter coming on for Pulisic to join his father Gregg as the second father-son pairing in USA World Cup history, after Claudio and Giovanni Reyna.
The USA next face Australia in Seattle on June 19, before closing the group against the winner of a UEFA play-off path on June 25. On this evidence, Pochettino's side will go into both fixtures as clear favourites — provided their captain is fit to lead them out again.