Strange times in Catalonia. On the European front, things have been relatively straightforward. A potentially tricky group containing Ajax, AC Milan and Celtic was negotiated with a minimum of fuss — one shock loss in Amsterdam aside — and their last-16 opponents Manchester City were spirited but never once looked capable of winning the tie.
At home, though, things have been much choppier. For a team that in recent times has viewed second place as a failure, their current third position might almost be considered a crisis. Tata Martino's side have shown flashes of the usual brilliance but also a new and exciting vulnerability; recent home thrashings of Osasuna (7-0) and Almeria (4-1) have been interspersed with consecutive away losses at Real Sociedad (1-3) and Real Valladolid (0-1). Add to that the fallout from the revelations that the purchase of Neymar was more than a little murky, and the persistent rumours that Martino will be on his way at the end of the season, and there probably hasn't been a better time to play Barcelona in years.
But. They still have Lionel Messi, who is to other footballers as other footballers are to ordinary humans. They also have Neymar, Alexis Sanchez, Pedro, Cesc Fabregas, and Andres Iniesta, who are merely varying shades of brilliant. And the last time they failed to reach the semi-finals of the Champions League was 2006-07; should they tumble out at this stage now, it might truly signal the end of the team that Pep built.
If Barcelona are a team playing a touch below their capabilities, their opponents Atlético Madrid are playing at the very extremity of theirs. Built in the terrifying, captivating image of their coach Diego Simeone, though they lack the glamorous names and reputations of their opponents, they tackle hard, break quickly, pass intelligently, and defend like absolute lunatics. In Arda Turan and Diego Costa they have the attacking capacity to hurt any side, and though there's no evidence to support this, surely the superior coolness of their shirt sponsor will give them an edge. "Qatar Foundation" vs. "Azerbaijan: Land of Fire"; that's not even fair.
One place and one point above Barcelona in Spain, their progress through the Champions League has been admirably smooth, particularly for a side that weren't even in the competition last season. Undefeated in their group, their last-16 tie against AC Milan was a masterclass in European football: a narrow 1-0 win in Italy, followed by a 4-1 romp at home. Milan are, admittedly, a shambles, but for a team not used to the sharper end of the Champions League, things could not be going better.
Barcelona: Xavi - There have been whispers for a couple of seasons that the most quietly remarkable footballer of his generation might, at long last, be starting to decline. Against a midfield as tigerish as Atlético's, space and time will both be at a premium, and Xavi may struggle to get his side's passing going.
Atlético Madrid: Diego Costa - Well, obviously. Atlético are going to get chances — this Barcelona defence is a strange, motley, incoherent beast — and they are lucky that the Braniard whose job it is to take those chances is one of the form strikers in the world, having scored 29 goals in 31 games this season. He's also something of an expert at the darker arts of forward play, excelling at both the flamboyant descent to the turf, and the consequent expression of wounded outrage when he doesn't receive the decision
Lionel Messi vs. Thibaut Courtois - Barcelona and Atlético have played one another three times this season, twice in the Spanish Supercup and once in the league. All three games have been draws, two of them 0-0 and the other 1-1. So, goals are likely to be at something of a premium, and given the inevitability of Messi doing something at some point, Atletico's on-loan keeper will need to be at his best. Fortunately for his side, his best is very good indeed.