Both Barcelona and Real Madrid picked up victories in La Liga which means the Catalans stay one point above Los Merengues at the top.
Barca suffered at times but eventually overcame rock-bottom Xerez 3-1, who ended the game with nine men.
The Catalans began a crucial week with the right result, although the scoreline does not tell the whole story.
Pep Guardiola's makeshift side suffered some nervy moments at 2-1 before Zlatan Ibrahimovic scored the all-important third goal after 55 minutes.
Barca had looked comfortable following early goals from Jeffren Suarez and
Thierry Henry, but Mario Bermejo pulled one back immediately and Xerez missed a couple of great chances to level before Ibrahimovic's strike.
They now face a crucial game against Inter Milan in the UEFA Champions League in midweek.
Meanwhile, Kaka made a fairytale return to action as he emerged from the bench to net a late winner that keeps Real Madrid still firmly in the title race, following their 2-1 win at Real Zaragoza.
The Ј56million summer signing from AC Milan had missed the last six weeks with a groin problem but he was back with a bang, netting the decider against 10-man Real Zaragoza soon after appearing as a 75th-minute substitute.
Earlier, Madrid had taken a 50th-minute lead through Raul but relegation-battling Zaragoza, despite having Matteo Contini sent off two minutes later, still managed to draw level Adrian Colunga on the hour-mark.
That equaliser could have cost Madrid dear with Barcelona's victory earlier in the day, but Kaka's late strike keeps Manuel Pellegrini's men in touch with the Catalan club with four games now remaining.
In the other game on Saturday, Valencia picked up a 1-0 victory over Deportivo La Coruna at the Mestalla.
A David Villa penalty in the first-half was enough for Valencia who stay third ion the table, while Depor remain in ninth.
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