Espanyol defender Ruben Duarte is one of five youngsters who will train with the Spain squad in June.
Vicente Del Bosque named a 24-man squad for the friendly against Costa Rica and the Euro 2016 qualifier in Belarus, but he also explained that Duarte would be one of several others to join up with the group.
La Roja will meet on June 1st, but with several players unable to meet up with the squad until later in the month due to club commitments, more bodies were needed.
Duarte, 19, has made a handful of appearances for Espanyol this season as a left-back, although he has played for the club's youth teams as a central defender.
He featured promininetly in Espanyol's run to the Copa del Rey semi-final, impressing in matches against Valencia and Sevilla.
Valencia's exciting young left-back Jose Luis Gaya will also train with the Spain squad.
Malaga forward Juanmi, Celta Vigo's versatile defender Jonny Castro and Atletico Madrid's Saul Niguez will also join up with Del Bosque's squad.