Real Madrid restored their four-point lead over second-placed Barcelona with a 2-0 win against Osasuna in the Spanish Primera Liga on Sunday.
An early goal from Ruud van Nistelrooy maintained their 100 percent record at the Bernabeu this season and left them with a comfortable cushion over arch-rivals Barca, who they visit next weekend.
Wesley Sneijder made sure of the points midway through the second half against a limited but determined Osasuna.
Real have 38 points and Barca 34 after they saw off Valencia 3-0 at the Mestalla on Saturday.
Earlier, Atletico Madrid were held to a goalless draw at Recreativo Huelva but hung on to third place in the standings on 31 points.
Italian goalkeepers Christian Abbiati of Atletico and Stefano Sorrentino of Recre were the outstanding figures as Atletico in particular failed to take their chances.
Turkish striker Nihat Kahveci scored twice for Villarreal in a 3-1 away win at Getafe, that ended a run of three games without a win for Manuel Pellegrini's side. They went level on 31 points with Atletico in fourth.
Espanyol are fifth with 30 points, after their 1-0 win over bottom club Levante on Saturday, and Racing Santander stay sixth with 26 despite losing 2-1 at Real Murcia.
Elsewhere, Sevilla were held to goalless draw at Valladolid and new Real Betis coach Paco Chaparro made it two wins from two after his side overcame nine-man Almeria 3-1 at home with a double from Argentine striker Mariano Pavone.
Real took the lead against the run of play with their first effort in the 16th minute, when Sneijder's free kick found Van Nistelrooy unmarked in front of goal to head his eighth of the season.
The Navarrans continued to dominate possession and threatened from set pieces, but lacked the cutting edge to really test Real keeper Iker Casillas.
Robinho, Raul and Sneijder went close for Real as Bernd Schuster's side looked far sharper in front of goal, but it was not until the 76th minute that they sealed the victory.
Robinho spun clear of three markers in midfield to launch a counter-attack that finished with Dutchman Sneijder lashing the ball beyond keeper Ricardo.