On an emotional night that began with a minute's silence for the brothers, the Portuguese team shipped the first of four first-half goals in the second minute, with Gonzalez scoring twice for the reigning world and Nations League champions, and Vicky Gonzalez and Alexia Putellas adding the other two.
Portugal showed more composure in the second half, but they were no match for Spain's power, precision and technique and, though they held Spain at bay for most of the second half, Cristina Martin-Prieto scored with a superb late header to complete the rout.
With Italy having defeated Belgium 1-0 earlier in the evening, Spain top the group with the Italians second. Spain take on the Belgians in their next game, while Portugal face Italy.
Italy won their first match in the Euros since 2017 as Caruso struck in the 44th minute.
Lucia Di Guglielmo's quick pass from the right found Caruso unguarded just outside the box and the Bayern Munich midfielder calmly curled a right-footed shot away from keeper Lisa Lichtfus to find the net by the near post.
Players and fans from Portugal and Spain came together for a moment of silence ahead of their opening Euros match in honor of Diogo Jota and Andre Silva. pic.twitter.com/kgtBuTCmYi
— espnW (@espnW) July 3, 2025
"It was what we wanted, the first match is always complicated," coach Andrea Soncin told RAI after Italy made their first winning start in the tournament since 2009.
"We can definitely improve and we must if we want to continue to grow, but I am happy with the attitude we showed."
Player of the match Caruso probed the Belgian defence with multiple attempts in the first 20 minutes, after the match began with a minute's silence following the death of Portuguese national men's team striker Diogo Jota in a car accident.
Belgium had more of the ball in the first half and made 10 attempts, two more than Italy, but failed to take the lead when Mariam Toloba shot wide in the 26th minute and Tessa Wullaert missed the target from close range four minutes before Caruso's goal.
Lichtfus's quick reflexes saved Cristiana Girelli's close range back-flick in the 64th minute to keep Belgium in the game, but the 2022 quarter-finalists were unable to find an equaliser as Italy comfortably held on to ensure victory.
Italy will continue their campaign against Portugal on Monday, while Belgium play world champions Spain.
"Feet on the ground," Soncin cautioned.