Spain come into the second Europe vs. South America clash of the day as favourites. They will be looking to reach their second World Cup semi-final, 58 years after their first.
A win will help put an end to talk that they are still underachievers on the big stage.
They have recovered from a shock 1-0 loss to Switzerland, winning every match since then. The loss to Switzerland was their second in 52 matches.
If they go on to win the World Cup, they will be the first side to do so after losing their first game at the tournament.
Spain have proven to be both solid and disciplined, conceding just two goals and one yellow card.
The European champions are up against a Paraguay side that has conceded just once in the tournament so far. Their defence will need to remain solid if they are to handle the attacking prowess of Spain.
This is Paraguay's first quarterfinal at a World Cup; they'll be hoping to go at least one better as well.
Paraguay have struggled to score, netting just three times in their four games.
There are rumours that Fernando Llorente could be in contention to start up front alongside David Villa.
However, Vincente del Bosque has said that he will play Fernando Torres, despite his poor form. He is yet to score a goal this tournament and has contributed little to the team so far.
If Torres does start, Spain will be likely to stick with the same team for the third game in a row.
David Villa is having none of Torres's problems, he is the tournament's top scorer with four goals to his name so far.
Raul Albiol and Javier Martinez have both suffered injuries and may not be able to take their places on the bench.
Roque Santa Cruz, Lucas Barrios, and Nelson Valdez are yet to score in the tournament, something that will worry coach Gerardo Martino.
In fact, Santa Cruz hasn't scored a goal in his last 800 minutes of World Cup football.
Victor Caceres is available again after serving a one-match ban against Japan. If he does play, he will take Nestor Ortigoza's place.
Apart from this, Paraguay should remain unchanged from their last outing.
Head to Head
The teams have met three times, it finished 0-0 in both 1998 and 2002, whilst Spain ran out 3-1 winners, also in 2002.