For what seems the fiftieth time this season, Barcelona face difficult questions at the back. The board's refusal to sign a center back, coupled with the management's lack of trust in young faces - Andreu Fontas went out on loan, Alberto Botia was not bought back, and Marc Bartra was given very limited time - means the options are limited yet again.
Carles Puyol is 34 and his body cannot take the punishment of top-level football for much longer. His return is shrouded in mystery, but it's clear he won't be available for the foreseeable future. Javier Mascherano is out for six weeks, which places his return sometime before the Champions League final should Barca get there, but that provides little relief until then.
To get past the quarterfinals second leg, and then the semifinal, not to mention to finally wrap up La Liga, Masche and Puyol are probably not going to be available.
There is one other name that brings hope: Eric Abidal. It would be something if Abidal was ready and fit to lift the Champions League cup after fighting cancer - for the second time! That would be incredible - but I'd rather not burden him with any expectation. What he has done up to this point is legendary in itself. There is no need to expect more.
So taking that into account, it's clear Gerard Pique will take one spot in central defense, but who will be lining up next to him? The answer is probably one of Bartra, Alex Song, Sergio Busquets, or Adriano - and all men carry big questions.
The Question: Is he ready?
There seems to be no doubt in the minds of Cules that Bartra is the real deal. He's talented, sure, but is he ready? "Yes," they would say. But is that just wishful thinking?
Bartra has been pretty good so far, though perhaps not exceptional. However, can such an inexperienced player be trusted at the biggest stage? Bartra has made nine La Liga appearances in his life. He's tall and composed but is he really ready to go into Champions League semifinals and win?
The Question: Has he learned?
Barcelona were priced out of buying Javi Martinez, who went to Bayern Munich for around $50 million, and Thiago Silva,who now is playing for PSG against the Catalans. The front office turned to Alex Song, who came from Arsenal for about $25 million. Ostensibly he could play midfield or defense.
The reality? Song has been getting progressively better as Busquets's backup at holding midfield, but in defense he's been a disappointment.
Tito Vilanova dropped Song when Pique and Puyol were unavailable for the league match up against Real Madrid in favor of Adriano, who had never played centerback in his life.
"He understands the tactical concepts," Vilanova said, "but he still needs time to execute them." Song always seemed to be dancing just a beat behind, struggling to keep up. This has changed in his preferred position, as he now seems snappier in his latest appearances in midfield.
But he hasn't made an appearance at centerback in a very long time. Song is fast and tall, but is he awareness inadequate at this stage to play CB?
The Question: Is it worth moving him?
Busquets has slowly risen form under-appreciated but important player to bonafide star. He is indisputable in the starting XI, cutting off opposing teams and recycling possession. His close control is incredible, first touch superb. He intercepts opponents by reading the game to perfection, and as a bonus, he's tall enough to play CB.
So what's the problem?
Well, the first is his speed is not optimal. But even more so, it's that playing in central defense Busquets is not as comfortable, and at the same time moving him away from defensive midfield opens up another hole. True, Song can play there, but that would be a downgrade. And at the same time, Busquets's quality would decrease playing out of position. Is it worth the price?
The Question: Can he stay healthy?
Adriano is nothing if not adaptable. He can play on either flank with ease. He can play fullback, midfielder, or forward. He can score beautiful goals and make key tackles.
Vilanova asked him to play in central defense, despite the fact the Brazilian international had never played there. Adriano was at the back when Barca drew against Real Madrid in the league, and he earned kudos for a brave display.
Adriano is fast, which was a key reason for Vilanova trusting him to play there. Certainly, a bit of added pace in defense can't hurt.
The only criticism is Adriano is not very tall, and he is dwarfed by the likes of Zlatan Ibrahimovic. Still, he's not much smaller than Mascherano, who did OK in the first leg.
The biggest problem for Adriano, actually, is that he seemingly cannot stay healthy. His Barca career has been marred by intermittent injuries. He was injured for the match in Paris, in fact, though he should be ready to go very soon.
Can Barcelona rely on a guy who is apparently made of glass?
The Question: Who??
Past those options, it's hard to imagine who can play centerback. Marc Muniesa has recovered from a serious injury that has kept him out for most of the season. He's been doing all right with the B team but surely Bartra is better equipped to step in? Keep in mind the B team is allowing goals by the truckload in Segunda Division - there probably aren't too many calls to get Sergi Gomez or David Lomban playing time.
As far as another player coming in to cover in the senior team, well, Dani Alves has offered his services for centerback and either Martin Montoya or Jordi Alba could hypothetically move over to the middle... but surely Adriano is a better option in that case?
And I know Lionel Messi would probably be a genius even in central defense, but there aren't too many other candidates that spring to mind. Unless Victor Valdes wants to leave his goal and become a full-time sweeper (I jest), I just don't see any other solution.
Who will play?
So in the absence of Puyol and Mascherano, who has the right tools? Tell us what you think in the poll and comments!