The Spaniard sustained a hamstring injury in training this week and will miss out against the high-flying Royals.
Tykes manager Simon Davey is already without striker Iain Hume (fractured skull), defender Darren Moore (groin) and winger Martin Devaney (ankle), who are all long-term absentees.
Striker Miguel Mostto has missed the last two matches through injury, but returned to training on Thursday and could be included in the squad.
Jamie Cureton, on loan from Norwich, is hoping to make his first start for the Tykes and he could partner Jon Macken or Kayode Odejayi up front.
Striker Michael Coulson will be included on the bench again alongside Marciano Van Homoet.
Reading boss Steve Coppell is expected to stick with the side that beat Coventry 3-1 on Monday.
Veteran centre-back Michael Duberry is set to keep his place in the centre of defence as Andre Bikey serves the second game of a three-match ban.
The Royals have long-term injuries to striker Dave Mooney and defender Sam Sodje, but club skipper Graeme Murty is edging closer to a first-team return.
Coppell said: "I think that every player wants to know that if he plays well and the team is winning then he is going to be in the team next week."
Reading are currently third in the Championship ahead of the trip to face Simon Davey's men at Oakwell.
Sporting Life.