Luis Suárez has declared that Spain's players "are only human and have to lose a match one day" ahead of Uruguay's friendly with 'La Roja' in Qatar on Wednesday evening.
The Liverpool and Uruguay striker lavished Vicente Del Bosque's side with praise in an interview, but still believes his side can beat them.
"They are not just difficult to beat, but their players are intelligent and have a lot of quality and they see things before their opponents do, and that's what makes them different from the rest," said Suárez.
The forward said Spain "have already shown that they are the best team in the world in recent years, and that's what makes them so hard to beat, because their players have so much confidence and their opponents respect them too much".
But Suárez added: "They are human and they have to lose some time, and they have lost in the past. But people shouldn't criticise them every time they lose because they have shown how much quality they have."
He also admitted that it will be difficult for his country, who reached the semi-finals of the 2010 World Cup, to qualify for the 2014 World Cup in Brazil.
"It's very difficult for us. The most important thing is that the team stays United. We have a squad that has been together for a long time and we know exactly what we want to achieve, which is improving game by game and showing that we want to reach the World Cup."
Uruguay won the Copa América in 2011 but had a disappointing 2012, and have gained just one point from their last four games in World Cup qualifying, which has left them fifth in their group.
They must finish among the top four to be guaranteed a place in the World Cup.