David Nalbandian will be out for the next few weeks with a leg injury suffered during his three-set win against Daniel Gimeno-Traver in the second round.
The injury was described as a three-millimetre tear in his adductor.
Nalbandian has pulled out of his quarterfinal match at Buenos Aires, as well as the ATP event in Acapulco and Argentina's Davis Cup tie against Sweden in March.
The withdrawal leaves the Argentine team without either of its two top players, with Juan Martin del Potro having also pulled out of the tie with a wrist injury.
Nalbandian was playing his first tournament since undergoing hip surgery early last year, having already had his attempted comeback in January derailed by an abdominal injury.