Either they are injury-prone or are suffering a dip in form, which is a problem for Tito Vilanova, the Primera Liga side manager.
Barca must find a way to plug leaky defence
Barcelona look badly exposed in central defence. For a side with the highest squad salary in world football, they lack cover in crucial central defensive options.
Carles Puyol is injury prone and 35, his usual foil Gerard Pique suffered a dip in form last season. A third option, Eric Abidal, had surgery for cancer and then a liver transplant which he is still recovering from. Everyone hopes he returns to play again, but there are no guarantees for the 33 year old.
Barca went into the clasico without a single recognised top-flight defender. Javier Mascherano has played beyond himself in defence on numerous occasions, but he is just 5ft 9ins (1.74m) tall. New signing Alex Song has looked awkward in defence, perhaps because he is not a defender.
Other central defenders such as Marc Muniesa, 20, Andreu Fontas 22, or Marc Bartra, 21, may have expected to start against Real Madrid, but Tito Vilanova went with Adriano, a full-back, at the heart of defence. It didn't work.
If Vilanova has no faith in the talented young Spain Under 21 defenders, why have them in his squad? If he does, why not give them minutes in lesser games to give them experience? The average height in Barca's defence on Sunday was a minuscule 5ft 7ins (1.71m).
Madrid's not especially big defence averaged 5ft 11ins (1.81m).
The Catalans have been linked with David Luiz and Nemanja Vidic. Whether it is promoting youth or buying a player, they need one more central defender they can trust.
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