Cubarsi headlines Spain squad for Paris Olympics
The 17-year-old centre-back was named in Luis de la Fuente's provisional squad for Euro 2024 but was cut ahead of La Roja's final party being announced.
He is joined by Eric Garcia, who spent last season on loan at Girona, while Fermin Lopez and Alex Baena are included despite being at Euro 2024 with the senior team.
Head coach Santi Denia was able to select players under the age of 23, with Manchester City's Sergio Gomez, Sporting CP's Abel Ruiz and Real Betis left-back Juan Miranda taking the three overage spots.
The likes of Yamal, Williams and Pedri were eligible but have not been chosen in what is initially a 22-man squad but must be cut to 18 ahead of the Games.
Spain took silver at the delayed 2020 Games in Tokyo three years ago, losing 2-1 in extra time to Brazil in the gold medal match.
For this year's competition, they have been drawn alongside Uzbekistan, Egypt and the Dominican Republic in Group C, facing the former in their first match on July 24.
Provisional Spain squad: Arnau Tenas (Paris Saint-Germain), Joan Garcia (Espanyol), Alejandro Iturbe (Atletico Madrid), Marc Pubill (Almeria), Juanlu Sanchez (Sevilla), Eric Garcia (Barcelona), Cristhian Mosquera (Valencia), Pau Cubarsi (Barcelona), Jon Pacheco (Real Sociedad), Juan Miranda (Real Betis), Miguel Gutierrez (Girona), Adrian Bernabe (Parma), Benat Turrientes (Real Sociedad), Alex Baena (Villarreal), Pablo Barrios (Atletico Madrid), Aimar Oroz (Osasuna), Sergio Gomez (Manchester City), Fermin Lopez (Barcelona), Diego Lopez (Valencia), Sergio Camello (Rayo Vallecano), Samu Omorodion (Atletico Madrid), Abel Ruiz (Braga).