Second-half goals from Adrian Lopez and Santi Cazorla were enough to hand a makeshift Spain side a 2-0 victory over Serbia in Saint Gallen.
Spain boss Vincente Del Bosque was without much of his squad as Barcelona and Athletic Bilbao were busy contesting the Copa del Rey final on Friday evening.
But the 2010 World Cup winners stepped up their preparation to defend their European crown as they cruised past the Serbs in this friendly in Switzerland.
La Furia Roja didn't have it all their own way in the first half - Xabi Alonso coming closest to breaking the deadlock before the break with an audacious effort from well inside his own half.
It was the introduction of Atletico Madrid forward Adrian, on his international debut, after the interval that provided the spark the world champions needed.
He headed home Jesus Navas' teasing cross and was then brought down by Branislav Ivanovic to allow Cazorla to seal the victory from the penalty spot with a quarter of an hour remaining.
Del Bosque surprised many with his selection, opting for a 4-4-2 system with Alvaro Negredo and Roberto Soldado in attack.
Juanfran also made his debut at right-back, whilst the other four uncapped players in the squad remained on the bench.
Negredo had more of an impact than Soldado, twice going close in the early stages, but that was about as exciting as it got.
At the other end, Serbia's only attack saw Dejan Lekic put the ball in the net but he had already been rightly flagged for offside.
Spain were much improved when Negredo, Soldado, Alonso and Sergio Ramos were all replaced at half-time by newcomers Alvaro Dominguez and Benat as well as Adrian and David Silva.
And that could give Del Bosque food for thought as he must name his final 23-man squad on Sunday ahead of two more friendlies against South Korea and China.
The Spanish begin the defence of their European crown against Italy on June 10th.