Vicente Del Bosque's side were put through their paces at their secluded training camp in Gniewino, near the Baltic port city of Gdansk in northern Poland, cheered on by some 300 Polish fans and about 40 travelling Spanish supporters.
The outfield players -- who included their two minor injury worries fullback Alvaro Arbeloa and striker Jesus Navas -- trained to a rousing chorus of "Guantanamera" from the stands.
Among the spectators was student Gonzalo Panadero, who had travelled the 70 kilometres (44 miles) from Gdansk where he is studying psychology on a one-year exchange programme.
"Defending the title will be difficult. But we will go far," he said confidently.
Spain have been drawn in Group C with Croatia, the Republic of Ireland and Italy and take on the Azzurri in Gdansk on Sunday.
Italy, who are based in the southern Polish city of Krakow, on Wednesday visited the former Nazi German death camp at Auschwitz-Birkenau, where 1.3 million people, most of them Jews, perished in World War II.
Dressed in blue and white team tracksuits, they visited the barracks, the wall where prisoners were shot, before going to the gas chambers in nearby Birkenau three kilometres away and the largely destroyed crematorium where victims' bodies were burned.
They then placed a commemorative wreath inscribed with the words "Federazione Italiana Giuoco Calcio" -- Italian football federation -- at the memorial.
"Such an atrocity should never happen again. What happened here doesn't just concern one people. It concerns all of humanity. Their pain is our pain," the Italians wrote in the visitors' book.
They were later followed by players from the Netherlands, who made the same tour.
A delegation from the German football federation, including coach Joachim Loew, team manager Oliver Bierhoff, captain Philipp Lahm and Polish-born players Miroslav Klose and Lukas Podolski, visited the Auschwitz museum last Friday.
England, who are also setting up their base in Krakow, are also expected to visit after they arrive on Wednesday.
Roy Hodgson's first Group D opponents France were due to arrive at their impressive base near Donetsk, Ukraine later on Wednesday. Sweden, 2-1 winners over Serbia in a friendly on Tuesday, were expected in Kiev about the same time.
Laurent Blanc's France fly to Ukraine on a high after a 4-0 friendly win over Estonia on Tuesday and are hoping to erase memories of a 2010 World Cup, which saw a player mutiny against coach Raymond Domenech and a humiliating first-round exit.
Ukraine, though, enter the championship on a low note, losing their friendly 2-0 to Turkey in Ingolstadt, southern Germany, on Tuesday.
Coach Oleg Blokhin blamed the defeat on a bout of food poisoning that affected 10 of his squad, dismissing fears about his team's poor form going into the tournament and their first game against Sweden on Monday.
Ukrainian football chief Grigory Surkis, though, has given the home side a major incentive, offering players a 500,000-euro ($624,000, 405,000-pound) bonus for every group stage win and 250,000 euros for a draw.
Surkis added the team will get a two-million-euro bonus for making the knockout stages and the same amount for reaching the semi-finals. An appearance in the final will earn them three million euros extra and 4.5 million euros if they win.
"We have a better prize fund than any other team at the European championships," Ukraine's football supremo was quoted as saying by local media.