Leaders Real Madrid beat their arch-rivals and closest challengers Barcelona 1-0 at the Nou Camp to take a vice-like hold on the Spanish Primera Liga title race on Sunday.
Julio Baptista's well-taken first-half goal secured the Spanish champions only their second league victory in 24 years at Barca's ground, ended the Catalans' 100 percent home record this season, and sent them seven points clear at the top.
Real looked sharper throughout while Barcelona appeared paralysed with nerves and offered little once their visitors had edged ahead.
Bernd Schuster, after his first 'clasico' as coach, goes into the mid-season break sitting pretty with 41 points. Barca are second with 34.
Earlier, Espanyol came from behind to beat nine-man Atletico Madrid 2-1 away to climb to third on 33.
Portugal's Simao Sabrosa had given Atletico a first-half lead with a superb freekick, despite them being down to 10 men following the red card shown to their Argentine top scorer Sergio Aguero.
Raul Tamudo levelled just after the restart and with Atletico reduced to nine soon after when Mariano Pernia was dismissed, Luis Garcia raced on to Ivan de la Pena's pass to strike the winner with five minutes left.
Villarreal, who were held 1-1 at home by Recreativo Huelva, are fourth with 32, one ahead of Atletico who slipped to fifth.