Haven't really see any of Bilbao's game but from what i know they are a really good team with some great and talented young players. But as Portuguese, and even though, my team is FC Porto, i will support Sporting. But i think it will be difficult. If it was Porto and Benfica i would strongly believe, even though both of them are not at the best shape .. but we are talking about Sporting, that even though it's still a great team and one of the most important in Portugal, has been struggling to gain some stability. But the league isn't really going that good for them, so these 2 match will be really important for them ... so everything can happen.
BTW, once again Portuguese teams prejudiced against England's teams. I haven't really see Benfica's match against Chelsea, but undoubtedly they have reasons to protest at least at the first match, where a clear penalty wasn't marked. The same happened with Porto against Man City. Don't remember well, but back at the first game one of Man City should had been expelled, because of a second yellow card, and the referee didn't do anything ... when minutes before had showned an yellows card to Alvaro Pereira for a really similar situation, that forbid him to play the second game in England. And the second game ... City doing faults, Porto protesting .. and in the end Porto receiving all the yellow cards ... when dangerous fault's didn't get any repression by the referee.
To say that the Portuguese's were always pretty unlucky. I mean a lot of players injured *just to see the fact that Benfica had to play without any "true" central defender. And for example Porto had players like Mangala, Danilo injured ... and not to talk about the games itself where both Porto and Benfica play better, but both Chelsea and City have the luck of the game... Don't see any hope or interest on the match between Chelsea and Barcelona ... Barcelona will be on the final .. though against who .. i don't know. Going to be an awesome match .. RM against BM. Hope RM defeats them and wins the CL. I hope Ronaldo wins the best player trophy next year. With the most likely win of la liga and the win of CL and a good campaign i think he can win that trophy .. though we can't really say anything cuz there were already some similiar cases, i think Sneijder, and in the end Messi's won, not fairly imo.