Ivan Helguera has warned Spain to not show signs of complacency when they kick off their Euro 2012 campaign against Italy on Sunday evening.

The Azzurri have seen their preparations for the tournament undermined by the Scommessopoli scandal and injuries to key personnel, while they were comprehensively beaten by Russia in their final warm-up fixture.

However, Helguera was quick to point out that the Italians are often at their most dangerous when they are seemingly at their most vulnerable.

"You must always respect them," the former Spain stopper told reporters after a charity game on Sunday.

"In major tournaments, Italy are Italy. Spain cannot afford to rely on anything, though they are playing very well."

Meanwhile, Helguera's former team-mate at club and international level, Fernando Morientes, is confident that Spain can become the first side to win three major tournaments in succession.

"This is the chance for them to make history and they are the favourites to win the Euros again," the ex-forward enthused. "It will not be easy - the Euros never are - but Spain are the big contender."

Coach Vicente Del Bosque has selected three centre forwards for the tournament in Fernando Torres, Alvaro Negredo and Fernado Llorente, but Morientes is unsure as to who should lead the line in Poland and Ukraine.

"Each one of the strikers is different and the decision is up to Del Bosque," he mused. "But for each match, each can contribute something. They can all offer different things."

Spain's eagerly-awaited Group C meeting with the Azzurri kicks off at 18:00CET on June 10.