Luis Enrique: We were exceptional but we still have room for improvement
Spain head coach Luis Enrique was understandably delighted with his team's display and was full of praise for debutant Alejandro Balde, goalscorer Marco Asensio and Rodri, who played in an unfamiliar central defensive role:
"When things work out exactly as you'd hoped, it's an amazing feeling. We were exceptional in our control of the ball and at stopping them from causing us problems."
"Our objective in every single game is to dominate the game and to do that, you have to have the ball. We want our opponents to find it hard to play against us and get frustrated. Our pressing was so good today too. But we still have room for improvement."
"We know that Rodri has the skillset to play in central defence. He's a complete player, which makes his very versatile. I'm lucky to have so many players that can play different roles and make a big contribution."
"I don't like playing with the same team in every game. We're not here to just play with 11 players. I don't think I've ever named an unchanged team."
"We want to have lots of positivity around the team, which is great but tomorrow we'll start thinking about the Germany game. We're not going to win every game by such a big margin."
"It was the perfect moment to give Balde his debut. It was good to give Alba, and Busquets too, a rest. We've not had much time to work with Balde but he was flying."
"Asensio was incredible. He's full of confidence, his all-round play was fantastic. He's a top player."
Carlos Soler: We could've scored even more goals
PSG midfielder Carlos Soler came off the bench to score in the second half and urged caution despite the excellent display:
"We're really happy. Obviously, we never imagined we'd win by such a big margin. We could've scored even more goals but we played really well."
"We saw that Japan had won against Germany. It's a really tough group, we're going to have two difficult games."
"Everything came off for us from the very start of the game. We were well ahead at half-time and we spoke at half-time about goals being important."
"We're all trying to help the team. Everyone on the roster thinks they have a chance to play and gives their all whether they're starting or coming off the bench."
"It's normal that everyone is getting excited but we have to be cautious, it's only the first game. We know that Germany are Germany, Japan will be tough too."
Olmo: We played a fantastic game from the first whistle
Dani Olmo, who opened the scoring, was next up in front of the mic:
"We played a fantastic game from the first whistle. It was incredible, we're really happy."
"We wanted to control the game from the start and that's what we did. The heat affected them and we were able to create more."
"There's still a long way to go. We're really happy with the win but now we've got to think about Germany. We've got to prepare for it as if it were a cup final. If we win, we'll be close to getting through."
Half-time: Spain 3-0 Costa Rica
As close to perfection as you get from Spain! Luis Enrique will be absolutely delighted with that performance as his team have controlled possession superbly but have also had a cutting edge to go with it. The fluid front three of Olmo, Ferran and Asensio have constantly evaded the Costa Rica defence, with Pedri and Gavi in particularly getting forward in support of them at every opportunity.
Costa Rica have barely had an opportunity to play any actual football, they've spent the vast majority of the half chasing after their opponents, who've suffocated them any time they've been in possession.
Where does Luis Fernando Suárez go from here? Luis Enrique will want more of the same in the second half although he'll almost certainly have the luxury of resting players for the upcoming games if he wishes to do so.