Should be a very good game. Although I'm afraid that Barca wouldn't be able to replicate their performance in the last match up between the two. Simeone specializes in these knockout games and I think that Atletico would go on to the next round as Barca are very inconsistent this season. I just hope that Enrique sticks to a formation and stop with the constant rotation of the players.
Don't think he's underrated, he was very highly regarded last season at Sevilla by everyone. He started off at Barca excellently too, faded a bit, but has come back and been fantastic again the last few weeks when he's played.