Coach Pep Guardiola, who has watched city rivals Espanyol and Inter Milan shut down his side's passing game, has little margin for error as he pushes Barca towards the defence of their European and La Liga titles.
Espanyol coach Mauricio Pochettino outwitted Guardiola last weekend when they battled to a 0-0 draw with a turbo-charged pressing game, a result that allowed Real Madrid to close to within a point with five matches remaining.
Inter's Jose Mourinho went one better on Tuesday, exposing a surprisingly weak Barca defence after starving playmakers Xavi and Lionel Messi with a suffocating, robust approach.
Barca's Zlatan Ibrahimovic continues to divide opinion with his inconsistent contributions, while Thierry Henry and Bojan Krkic have been assigned bit-part roles of late.
Guardiola's decision to finish Tuesday's game with centre-back Gerard Pique playing as an auxiliary striker raised eyebrows with more recognised front men on the bench.
While he will be keen to rotate his squad against Xerez ahead of next Wednesday's return leg against Inter, the Barca coach he will be wary of a slip up against the wily Nestor Gorosito.
The Argentine has turned La Liga's whipping boys into a side with an outside chance of avoiding the drop. Xerez have only lost one of their last seven games and are six points from safety.
ENVIOUS EYES
Real Madrid will have watched Inter's performance with envious eyes and were surely lifted by the thought Barca could stumble again.
Manuel Pellegrini's side, who are effectively two points behind Barca due to the leaders holding the edge in the head-to-head record between the clubs, face relegation-threatened Real Zaragoza (16th) on Saturday.
Real hammered Zaragoza 6-0 at the Bernabeu back in December.
"We are in a much better situation than we were last week. We are only one point behind Barca and anything can happen in football," Cristiano Ronaldo was quoted as saying in Spanish media on Thursday.
"I am confident we can win our last five games and that if we do we will win the championship."
Pellegrini could be boosted by the return of Brazil playmaker Kaka, who has returned to training with the rest of the squad after injury.
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