With the two Spanish giants locked on 74 points, it is Madrid's stunning goalscoring that is currently giving them the slight edge, with their tally of 81 goals from 29 games being 10 more than Barca and giving the capital club a +2 goal difference over their arch rivals.

However, Barca presently hold the upper hand in the head-to-head record having between Madrid 1-0 at the Nou Camp in November, and if Pep Guardiola's side can avoid defeat at the Bernabeu that could prove crucial in the final reckoning.

Before 'El Clasico', though, there is another round of fixtures, when Madrid travel to struggling Racing and Barca host sixth-placed Athletic Bilbao.

And Madrid defender Marcelo knows it would be a mistake to look too far ahead.

"We have to go game by game. We can't think about Barcelona. When the week of the Clasico arrives, I'll look at Barcelona, but not until then," said the Brazilian, whose in-form side became the first team in La Liga to score three or more goals in 10 successive games when they defeated Atletico 3-2 last weekend.

"We have to think about Racing because life could become complicated if we think about another game."

More positive news for Madrid coach Manuel Pellegrini came with the return to training today of French duo Karim Benzema and Lassana Diarra after injuries, although Kaka was still missing.

Barca look to have the trickier game on paper as opponents Athletic are in the hunt for a top-four finish, but the Catalan giants will be brimming with confidence following their Champions League clash with Arsenal last night.

The reigning European champions may have had to settle for a 2-2 draw at Emirates Stadium after being 2-0 up but their performance was stunning.

"Last year we won everything but we didn't play away like we did here," said Barca coach Guardiola after the game.

"We displayed our best football and did all we could to take a major step forward."

Aside from the Barca-Athletic match, there are two other games on Saturday.

Real Zaragoza, in 17th, have the chance to climb above 15th-placed opponents Malaga if they can build on last weekend's impressive 3-0 home win over Valencia, while struggling Sevilla will hope to avoid more disappointment when they host third-bottom Tenerife.

Sevilla's 3-0 defeat at Villarreal in the first game under interim coach Antonio Alvarez last Sunday left the Andalusian side without a win in eight competitive matches, although they could climb back into the Champions League spots with a win this weekend.

That would require fourth-placed Real Mallorca to drop points at Almeria but, with an away record that has brought the Balearic island club just two wins all season, Sevilla will hope for some good news at long last.

Also on Sunday, Villarreal could move to within two points of the Europa League places if Athletic lose at the Nou Camp and the Yellow Submarine overcome second-bottom Real Valladolid.

Valencia and Atletico Madrid, who meet in the Europa League tonight, have home games this weekend against Osasuna and Deportivo La Coruna respectively.

Elsewhere, bottom club Xerez will hope to continue their improved form when they go to Sporting Gijon and Getafe meet Espanyol.