Real Madrid [Images] failed to keep the pressure on Primera Liga leaders Barcelona as they were held to a 1-1 draw at the Bernabeu by relegation-threatened Real Sociedad on Saturday.

Brazil [Images] striker Ronaldo [Images] scored his 100th goal for Real in the first half, but Sociedad's impressive Mark Gonzalez pounced on an error by goalkeeper Iker Casillas to equalise after the break as the home side faltered.

Real closed to within 10 points of Barcelona, who visit Racing Santander on Sunday. Valencia, who are three points behind Real in third, play at Celta Vigo later on Saturday.

Sociedad's point put them level on 32 with Real Mallorca and Alaves, who both play on Sunday, but they remain in 18th place.

The bottom two, Cadiz and Malaga, were earlier pushed closer to relegation after late goals denied them points.

Cadiz, 19th on 28 points, were close to victory against regional rivals Betis after Argentine striker Lucas Lobos scored a penalty, but with a minute remaining Betis equalised when Joaquin got his head to Marcos Assuncao's free kick.

Getafe's Veljko Paunovic scored both goals for the visitors as they beat Malaga 2-1 to leave the Andalucians bottom with 23 points.

The bottom three clubs are relegated at the end of the season.

CASILLAS ERROR

Sociedad, who have the worst away record in the league, were determined to take the game to Madrid and unsettled the home defence early on with a string of teasing crosses before Ronaldo scored in the 25th minute.

Zinedine Zidane [Images] picked out the Brazilian on the edge of the area with a low free kick and he fired a first time shot into the far corner for his fourth goal in as many games.

Five minutes later Ronaldo almost had his second when he finished off a swift break by shooting against a post, and then scooping the rebound over an empty net.

Sociedad continued to have chances, however, and Chilean winger Gonzalez stung Casillas's fingers with a rasping free kick just before the break.

In the 62nd minute Casillas fumbled Mikel Alonso's harmless cross and Gonzalez was on hand to poke home the loose ball for the equaliser.

Five minutes earlier Ronaldo had limped off injured to be replaced by Italy [Images] striker Antonio Cassano, but Real clearly missed the Brazilian's presence as they chased the winner.

Brazilian forward Robinho led Real's charge near the end but they lacked precision and lost their way when midfielder Guti was sent off four minutes from time.

Real left the pitch to a barrage of whistles from disgruntled home fans.

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