Jose Mourinho sat through a Real Madrid news conference in complete silence yesterday, refusing to answer questions ahead of his team's Spanish league match against Barcelona.

Mourinho sat stonefaced beside assistant Aitor Karanka, who answered questions. Mourinho's refusal to speak led to a number of journalists walking out of the news conference in protest.

The Portuguese coach certainly wrote himself into derby history with the stunt. Mourinho is already a part of recent Barcelona folklore after heated Champions League series between the Catalan club and the Chelsea and Inter teams he coached.

"It's a way of working," Karanka said. "It's not unusual that sometimes I come out. It's not a lack of respect toward anyone."

Karanka has taken questions instead of Mourinho 11 times this season but this was the second straight league game where the Portuguese coach did not speak in the build-up.

Barcelona will almost certainly clinch its third straight Spanish league title if they win the match at the Santiago Bernabeu Stadium with Madrid trailing by eight points with six games to play after this round. Barcelona are unbeaten for 29 games and have won five in a row against their biggest rivals.

The pair are meeting four times inside 18 days, including Wednesday's Copa del Rey final in Valencia and a two-legged Champions League semi-final series.

Barcelona won the last Spanish league meeting 5-0 in November to hand Mourinho the worst defeat of a career that includes two Champions League victories and domestic league titles in England, Italy and Portugal.

"Everyone knows the importance of the game," Karanka said. "The team has grown and matured a lot since the season's first clasico."

Real Madrid are without injured midfielders Lassana Diarra and Fernando Gago to injury and Esteban Granero to suspension. Mourinho left midfielders Pedro Leon and Sergio Canales out for technical reasons.