Lamine Yamal's return sparked Spain's World Cup into life as the European champions ran riot to beat Saudi Arabia 4-0 in Atlanta.
Making his first start in two months after a hamstring injury, Yamal ended La Roja's long wait for a World Cup goal just 10 minutes in.
Mikel Oyarzabal then struck twice to put Luis de la Fuente's men 3-0 up inside 24 minutes.
De la Fuente's careful management of Yamal's minutes continued as the Barcelona superstar was replaced at half-time before Hassan al-Tambakti's own goal rounded off the scoring.
Victory propels Spain to the top of Group H ahead of Uruguay's meeting with Cape Verde later on Sunday.
Billed as one of the pre-tournament favorites, Spain got off to a slow start in a 0-0 draw against debutants Cape Verde.
A pedestrian performance despite dominating possession only highlighted the importance of Yamal to their quest to be world champions for a second time.
De la Fuente also warned his players had been "stung" by the criticism they faced following their opening result and they responded emphatically.
Yamal's return was one of four changes in total with Pedro Porro, Dani Olmo and Alex Baena also coming into the starting line-up.
After over 2,500 passes and 50 attempts at goal since their last World Cup goal, Spain finally found the net and fittingly Yamal made the breakthrough.
- Pressure rises on Saudis -
Oyarzabal found space in behind the Saudi defense and his low cross picked out the 18-year-old to slot in at the back post.
Coach Georgios Donis looked particularly irked that two of Spain's goals came from corners.
Oyarzabal pounced on Aymeric Laporte's flick on to give the 2010 winners the breathing space they craved.
Just three minutes later, the Real Sociedad forward volleyed home from Dani Olmo's header for his 14th international goal in his last 13 caps.
Oyarzabal was inches away from a first half hat-trick when his audacious effort with the outside of his foot from a narrow angle came back off the crossbar.
But with the job done by half-time, De la Fuente could afford the luxury of replacing Yamal and Oyarzabal at the break.
The changes did not disrupt the waves of Spanish attack towards the Saudi goal, but the fourth also came via a corner.
Cucurella was afforded acres of space to shoot and although his effort was repelled by Mohammed al-Owais, the rebound deflected in off the unfortunate Tambakti.
To round off an ideal afternoon for De la Fuente on his 65th birthday, Nico Williams and Mikel Merino were afforded valuable minutes off the bench in the second period as they too get up to match speed after lengthy absences due to injury.
By contrast, the pressure is now on Donis to deliver in Saudi Arabia's final group game against Cape Verde in Houston.
Victory will likely take the Arabian Falcons into the knockout stages for the first time since the World Cup was last in the United States 32 years ago.
Spain travel to Guadalajara next for the final group game against two-time winners Uruguay on Friday.
