Roberto, 24, has scored six goals in six LaLiga games so far this season, with only Barcelona pair of Raphinha and Lamine Yamal, as well as Real Madrid's Kylian Mbappe, having recorded a better return.
Inter Milan goalkeeper Josep Martinez, whose only previous cap came in a friendly against Lithuania in 2021, has also earned a call-up with Barca's Joan Garcia injured.
Garcia is among four players missing from the World Cup squad alongside the retired Marcos Llorente, forward Borja Iglesias and Barca's Gavi.
The Catalans' midfielder Fermin Lopez returns to De la Fuente's set-up having missed the World Cup triumph due to injury.
Part of De la Fuente's squad announcement included a video filmed in Spain's North African exclave of Ceuta, which is grappling with a migration crisis.
The Spanish football federation said it was to show support to the city and people of Ceuta.
On Tuesday, France stars Mbappe and Ibrahima Konate and Brazilian striker Vinicius Junior, all of whom play for Real Madrid, rolled up pre-match t-shirts bearing the words 'We are all Ceutans', sparking outrage from conservative and far-right politicians in the country, before their league win over Elche.
La Roja travel to England on September 26th in their first game since lifting the World Cup in July before hosting Croatia three days later in Seville.
They entertain the Czech Republic in Oviedo on October 3rd and end the international window by heading to Croatia three days later.
Spain's Nation League squad:
Goalkeepers: Unai Simon (Athletic Bilbao), David Raya (Arsenal), Josep Martinez (Inter Milan)
Defenders: Pedro Porro (Tottenham), Marc Cucurella, Dean Huijsen (Real Madrid), Alejandro Grimaldo (Atletico Madrid), Pau Cubarsi (Barcelona), Marc Pubill (Atletico Madrid), Eric Garcia (Barcelona), Dean Huijsen (Real Madrid), Aymeric Laporte (Athletic Bilbao)
Midfielders: Rodri (Barcelona), Martin Zubimendi, Mikel Merino (both Arsenal), Fermin, Pedri (both Barcelona), Alex Baena (Atletico Madrid), Fabian Ruiz (PSG)
Attackers: Yeremy Pino (Crystal Palace), Victor Munoz (Liverpool), Mikel Oyarzabal (Real Sociedad), Dani Olmo, Lamine Yamal (both Barcelona), Ferran Torres (PSG), Roberto Fernandez (Espanyol), Nico Williams (Athletic Bilbao)
UEFA Nations League
The UEFA Nations League 2026/27 is contested by the national teams of 54 of UEFA's member associations. They're divided into four leagues based on the rankings of the previous edition, with Leagues A, B, and C featuring sixteen teams each, divided into four groups of four, while League D features six teams divided into two groups of three. It begins in September 2026, with the finals in June 2027.
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