The 29-year-old Argentinian limped out of the 3-1 midweek defeat at Derby with a groin problem and is a major doubt.
However, midfielder Kevin Thomson has a chance of making the squad after returning to training following his recovery from a fractured fibula.
Manager Gordon Strachan will hope to have options with his forwards with Scott McDonald looking to shake off the virus which kept him out of the game at Pride Park, where Kris Boyd scored on his return to the team alongside Leroy Lita.
However, Justin Hoyte (hamstring), Jonathan Franks (herniated disc), Willo Flood (knee) and Rhys Williams (pelvis) are still out, while loan signing Matt Kilgallon has returned to parent club Sunderland with a back problem.
Richard Hughes returns to the Portsmouth squad.
The midfielder has completed a two-match suspension for his red card against Leicester in the Carling Cup.
Hughes is unlikely to go back into the starting line-up, though, with Pompey having won both games in his absence to lift themselves out of the drop zone.
However, there is plenty of room on the bench with boss Steve Cotterill only able to name five substitutes against Bristol City on Tuesday night.
Cotterill's loan move for Tottenham's Kyle Naughton remains on hold so rookie Joel Ward continues at right-back.
Defender Hermann Hreidarsson (Achilles), striker Danny Webber (cruciate) and youngsters Tom Kilbey (knee) and Billy Goddard (shin) are still on the sidelines.
Source: DSG
Source: DSG