Barça has won eight, drawn one and lost just one game immediately after playing Real Madrid over the last three and a half seasons.
Guardiola's side is rarely caught off their guard after facing their biggest rivals. In fact, they have generally picked up great results the next time they have played. They have only been beaten once in such matches over the last season and a half.
In their most recent matches, Barça thrashed Al-Sadd (4-0) at the Clubs World Cup and also Napoli (5-0) in the Gamper after winning at the Bernabéu in the league and at the Camp Nou in the Spanish Supercup respectively. Last season, FCB won at the Reyno de Navarra 3-0 after their historic 5-0 demolition of Madrid, and Osasuna were again the victims, this time 2-0, straight after Barcelona had been beaten in the cup final. They also won the derby with Espanyol 2-0 immediately after putting Madrid out of the Champions League.
In Guardiola's first two seasons, clashes with Madrid were less frequent affairs. But in 2009/10, after beating Madrid home and away in the league, Barça defeated Xerez 2-0 and Deportivo 3-0 and the previous season won 2-1 against Vilarreal.
Paradoxically, Barça's best result after a clásico wasn't a win. It was the last-second draw at Stamford Bridge, which came just four days after winning at the Bernabéu 6-2 in May 2009. The win in London sent Barça into the Champions League final. The other time Barça failed to win immediately after a clásico was last season, when they lost at Anoeta, 2-1, but the result didn't matter too much, because the Catalans were already well on course for the league title, which they did indeed eventually win. (via FCBarcelona.cat)