Villarreal midfielder Bruno Soriano scored Porto as favorites in their league position in Europe in the semifinals.
However, Soriano believes that yellow submarines have the firepower to sink the recently crowned Portuguese champions.
Porto go to first stop Thursday at the Estádio do Dragão in great form, having won their last 12 games, but they are still unbeaten in the league after winning 25 and 27 games.
This has led Porto to win the title earlier this month, and last week defeated Benfica goals to advance to the final of the Cup of Portugal.
This has been a remarkable season primarily responsible for 33-year-old trainer Other Villas-Boas, and a good result against Villarreal on Thursday will push a bit more silverware even more possible.
With this in mind, Soriano believes that Villarreal are oppressed in the semifinals.
But with the Spanish team continued their first major trophy, the Spanish international does not exclude the chances of his team.
He said: "I think they are the favorites, and to win titles, but there is no doubt that we have this label, which does not affect us at all ..
"At this stage of the competition all teams must be respected. We both know it will be a very even tie and hope that things on our side.
"It will be difficult to get to the finals, because Porto is a very good team, but we hope to get a good result. We have a chance if we do things well."
Soriano is also supported by the strikers of their equipment due to the problems of Oporto.
Giuseppe Rossi scored 10 goals this season's competition - one fewer than Falcão Porto, which is the overall leader - while Nilmar thanked five times.
Soriano, whose team lost 3-2 against Sevilla at the weekend, but still comfortably placed fourth in the league, in www.superdeporte.es added: "We bow to Porto can fire torpedoes."
Porto boss Villas-Boas not agree that his team are favorites, said: "There are no favorites when we get to the semi-final, especially after the big teams have been eliminated.
"We know this is a tough game and I reject any suggestion of being favorites.
"I think that Villarreal is the most difficult team met on this trip. They play attacking football with a great quality, with a style that has been likened to Barcelona."
Winner of the road to face the opposition of the finals in Portugal, where Benfica Braga to take the other semi-final.