Perhaps the two biggest clubs in the world clash as Barcelona host Real Madrid in the second leg of the Copa del Rey quarter-finals on Wednesday at Camp Nou.

The first leg did not go Real Madrid's way.

Real Madrid went into halftime with a one-goal lead thanks to Cristiano Ronaldo. But Barcelona dominated the second half as the Catalans fought back at Santiago Bernabeu. A header from Carles Puyol and then a right-footed shot from inside the box from Eric Abidal was the difference, as Barcelona took another win at their rival's home.

Ronaldo was basically absent in the second half, as Real Madrid didn't appear to put up much of an attack. Barcelona had several chances, while Real Madrid failed to contain Barcelona's potent passing attack.

It was the second win for Barcelona over Real Madrid in recent weeks. On Dec. 10, Barcelona defeated Real Madrid, 3-1, after scoring three unanswered goals following a Karim Benzema goal in the first minute.

Now the rivalry has returned to Barcelona's home, making things very difficult for Los Blancos. Jose Mourinho's squad will need to win 2-1 to force penalty kicks, or defeat Barcelona by a convincing score, to advance to the semi-finals of the tournament.

For Barcelona, a victory will be a momentum boost for the club. The Catalans trail Real Madrid in the standings by five points, and when the two teams meet again in April for a La Liga match, the league title might be on the line.

Wednesday's lineups will also be interesting. Sami Khedira and Angel di Maria are sidelined with injuries. Mourinho might sit Pepe after the centre back stomped on Lionel Messi's hand in the second half of the Jan. 18 match.

Barcelona has been struck with a number of injuries this season. Both David Villa and Pedro are out, which means Alexis Sanchez will have to step up in their absence. Barcelona will also be without Seydou Keita, who is still away at the 2012 Africa Cup of Nations  

Pep Guardiola rotates his goalkeepers in this competition, and this time Jose Manuel Pinto will be starting.