Spain suffered a shock 1-0 defeat to a stoic Georgia in their final pre-Euro 2016 friendly at the Coliseum Alfonso Perez on Tuesday.
Confidence would have been high following comfortable wins over Bosnia-Herzegovina and South Korea in Spain's two prior warm-up fixtures, but Tornike Okriashvili consigned them to an unlikely defeat.
Aritz Aduriz failed to stake his claim for a starting spot in France, turning in a disappointing display in response to Alvaro Morata's double against Korea.
Thiago Alcantara rattled the post shortly before the half-hour mark, but Spain found themselves behind when Okriashvili punished some slack defending to tap beyond David de Gea, picked ahead of Iker Casillas with Vicente del Bosque's first-choice goalkeeper still unclear.
It was a rare attack from the visitors, who shut up shop in the second half and managed to see out a first win in seven matches as Spain struggled to forge meaningful openings.
Having suffered his first defeat since the 2-0 loss to Netherlands in March 2015, Del Bosque will be seeking an immediate response when Spain begin their European Championship defence against Group D rivals Czech Republic on Monday.
Having competed in the Champions League final on May 28, Spain's contingent of Real Madrid and Atletico Madrid players were available for selection for the first time in their pre-Euros programme.
Sergio Ramos, a member of that party of players, arrived too late to add a simple finish to Gerard Pique's flick on to the back post, before Cesc Fabregas slammed into the side netting following a slick move in the eighth minute.
Georgia could barely get out of their own half with Spain dominating possession, but they were let off the hook when Aduriz sent a powerful header wide following a cross from debutant Lucas Vazquez.
Thiago saw his low, curling strike come back off the base of the upright with 28 minutes on the clock, but Georgia became more adventurous as the half continued and a rapid break saw them take the lead before half-time.
Jordi Alba's stray pass near the halfway line was seized upon by Valeri Qazaishvili, who quickly initiated the counterattack that ended with Jaba Jigauri squaring from the right for Okriashvili, capitalising on Ramos' lax defending to tap home a simple finish.
The Madrid defender did not return for the second half as he was substituted for Mikel San Jose, while Fabregas' replacement, Andres Iniesta, fired wide within four minutes of the restart.
Sergio Busquets played on after a collision with Revishvili left him prone, but the Georgia goalkeeper was withdrawn for Roin Kvaskhvadze.
After scoring doubles against Bosnia and Korea, Nolito was unable to maintain his prolific form when he pulled a 25-yard strike wide in the 64th minute.
Spain continued to push and Alba cushioned a diagonal cross from substitute David Silva straight to Kvaskhvadze before Nolito missed the target again.
Pique steered a header beyond the post with three minutes of normal time remaining, with questions sure to be asked of Del Bosque's team following defeat to a team ranked 137th in the world.