Can the Real Madrid manager break Barcelona's stranglehold further? We will find out in the next six days.
Jose Mourinho's master plan is music to Real Madrid fans' ears
The fans leaving the cafes in the working class Barcelona suburb of Canyelles could not quite believe their ears.
Like the rest of Spain, they had just sat transfixed to a television screen for the second of the four clasico games in 18 days, this one the Copa del Rey final in neutral Valencia.
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Real had not beaten Barca since 2008, with the Catalans triumphing on six consecutive occasions until a 1-1 draw in a league fixture at the Bernabeu 10 days ago.
Four days later they finally recorded a victory, which led the Real fan to broadcast the club's Hala Madrid anthem through a lofty loudspeaker.
The speaker was situated on top of a public housing block and the most offensive noise most Catalans could hear echoed around the streets below.
Beating Barca to win the cup was a cathartic moment and the celebrations lasted until dawn in Valencia as the Barca fans melted away to ponder Jose Mourinho's challenge to their pre-eminence.
They do not like the Real manager because he is probably the only coach in the world who knows how to trip up their finely balanced football machine. The win galvanised Real, but Catalans hope it will not haunt Barca.
Round three of the four clasicos is tonight in Real's Bernabeu stadium in the Champions League semi-final first leg.
"Barcelona is the strongest team, but Mourinho's Madrid has more mental strength after winning the cup," said Francesco Coco, the former Barca and Italy midfielder.
Pep Guardiola, the Barca manager, is likely to be missing Eric Abidal, Adriano, Bojan, and Maxwell - almost a quarter of his first-team squad.
None of the absentees are as important as Lionel Messi or Xavi.
Carles Puyol, their captain, has recovered from a hamstring strain and will play.
He started his first game since January in the league match at the Bernabeu 10 days ago, but left the field before the hour mark with a troublesome hamstring. He was an unused substitute in the Copa del Rey final, with Javier Mascherano filling in as an emergency centre half.
"Madrid is the worst opponent we could play right now," said Sergio Busquets, but Barca still boast considerable riches.
Both Spanish giants have scored more goals (24) than any other team in this season's competition.
Real have yet to concede a goal at home in eight Champions League games this term, surpassing their own record in 1998 and 2002 - both years when they won the competition.
Real are the form team. Like Barca, they rested players on Saturday, but their fringe side still destroyed Valencia 6-3 away.
Pepe, the Portuguese centre-back, is available to play after a one-match ban but Ricardo Carvalho, his usual partner, is suspended for the first leg. Ronaldo, Sergio Ramos, Angel Di Maria and Raul Albiol are within a booking of a one-match ban.
Given that there have been 21 yellow cards in the three clasico games so far this season and that Real have had players sent off in each of the last three meetings with Barcelona, there could be serious implications for both clubs in the second legs if there are bans to key players.
A final appearance at London's Wembley stadium awaits for the winner, but so does the crown of kings of Spanish football.
Barca will win the Primera Liga, but Mourinho's team are getting stronger all the time and previously injured or out-of-form players like Gonzalo Higuain, Karim Benzema, Sergio Canales and Kaka are hitting their stride.
"I feel better than at any time since I arrived here," Benzema said.
"The longer our season goes the better," said Raul Albiol, the defender. "A weight has been lifted now that we have won the cup."
Can Real's new found confidence eclipse Barca's stuttering brilliance? Will the phantom public address announcer be back to taunt the people of Barcelona? Seconds out, round three.
Real Madrid v Barcelona match-up
Iker Casillas v Lionel Messi
In Casillas, below, Real have probably the best goalkeeper in the world. He has been superb in the two recent matches against Barca and, in what is likely to be a tight game, his ability to make the saves most keepers can’t will be key, with Messi so dangerous from outside the penalty area.
In this month’s previous two battles with Barcelona, Jose Mourinho has played Pepe, a centre-back, as a defensive midfielder to stifle Barca. It has worked, but Ricardo Carvalho’s absence at the back may force a rethink. Barca will play their usual intricate, stylish, patient short game. But are they as predictable as they are brilliant?
Real have beaten their rivals twice before at this stage en route to victories in 1960 and their last win in 2002. Tonight’s meeting is the third of four between the teams in 18 days. The pair drew 1-1 in the league before Real’s 1-0 extra-time Copa del Rey final win.
Real Madrid (4-4-2) Casillas; Arbeloa, Albiol, Ramos, Marcelo; Pepe, Alonso, Di Maria, Ozil; Ronaldo, Higuain
Barcelona (4-3-3) Valdes; Alves, Pique, Puyol, Mascherano; Busquets, Xavi, Iniesta; Messi, Pedro, Villa
• Lionel Messi became the first Spanish league player to score 50 goals in a season on Saturday and leads the Champions League with nine goals, but he has yet to score at the semi-final stage in three previous tries.
10.45pm, Aljazeera Sport +3