Spain are still favourites to finish top of Group E above Sweden, Poland and Slovakia but, after struggling to break down conservative sides such as Georgia and Greece in March, they know coming first will not be a procession.
Spain head into a major tournament with lower expectations than in recent years having no reliable goalkeeper, lacking a talismanic forward and missing injured captain Sergio Ramos but still believe they can beat anyone on their day.
Ramos, who was left out of their Euro 2020 squad in a jaw-dropping move by coach Luis Enrique, was the last survivor of the Spain side that ended 44 years without a trophy by winning Euro 2008 to start a glorious cycle of international dominance.
Luis Enrique has been criticised by sections of the Spanish media for the move but pointed to Real Madrid central defender Ramos's recent hapless run with injuries and said the move was "tough but taken for the good of the national team".
The coach also raised eyebrows for only picking 24 players out of a maximum 26 and not choosing one Real Madrid player.
Spain are still favourites to finish top of Group E above Sweden, Poland and Slovakia but, after struggling to break down conservative sides such as Georgia and Greece in March, they know coming first will not be a procession.
"Spain have a big problem in that when teams play us they change their system and their style, they give us the ball and it's like playing a different team," Luis Enrique told the Spain team's official website https://sefutbol.com.
Spain's squad is bursting with talent and experience, even without 35-year-old Ramos, but it lacks a bit of cohesion.
Their biggest concern is in goal. Number one Unai Simon looks uncomfortable on the ball and has had a poor season with Athletic Bilbao while making a few glaring errors for Spain.
Manchester United's David de Gea has long been vilified by the Spanish media, meaning Brighton & Hove Albion's Robert Sanchez has an outside chance of starting the tournament.
The situation is a far cry from when Spain could depend on the titanic presence of captain Iker Casillas between the posts, while, with the exception of Barcelona teenager Pedri, they also lack players who can pass their way through congested pitches as Xavi, Andres Iniesta and David Silva used to do for fun.
However, Luis Enrique does have plenty of players who can help the team adapt to the changing landscape of international football, which is ever-more physical and no longer suits a team of pass masters like the Spain side that collected two European Championship titles and the World Cup between 2008 and 2012.
Ateltico Madrid's Marcos Llorente is one of their most intriguing players after reinventing himself from a holding midfielder to a winger and Spain have a raft of other exciting forwards such as Gerard Moreno, Dani Olmo and Mikel Oyarzabal.
Then there is Ferran Torres, who scored a hat-trick in last November's incredible 6-0 rout of Germany.
"We're trying to recover and imitate the unique team that came before by making the players believe they can be champions too," Luis Enrique added.
"If we reach the level we're capable of we can aspire to anything."
Squad:
Goalkeepers: Unai Simon (Athletic Bilbao), David de Gea (Manchester United), Robert Sanchez (Brighton)
Defenders: Pau Torres (Villarreal), Eric Garcia (Manchester City), Aymeric Laporte (Manchester City), Diego Llorente (Leeds), Jordi Alba (Barcelona), Jose Luis Gaya (Valencia), Cesar Azpilicueta (Chelsea), Marcos Llorente (Atletico Madrid)
Midfielders: Sergio Busquets (Barcelona), Rodrigo (Manchester City), Thiago Alcantara (Liverpool), Pedri (Barcelona), Koke (Atletico Madrid), Fabian Ruiz (Napoli)
Forwards: Gerard Moreno (Villarreal), Ferran Torres (Manchester City), Adam Traore (Wolverhampton), Alvaro Morata (Juventus), Dani Olmo (RB Leipzig), Mikel Oyarzabal (Real Sociedad), Pablo Sarabia (Paris St Germain)
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