Simon replaces injured Gasquet on French Davis Cup team
France captain Arnaud Clement withdrew Gasquet, citing an unspecified injury, at the draw on Thursday.
In Friday's opening singles, Carlos Berlocq will face Jo-Wilfried Tsonga of France. Juan Monaco will play Simon in the second singles match on the outdoor clay at Parque Roca on the outskirts of the capital city.
David Nalbandian and Horacio Zeballos will play Julian Benneteau and Michael Llodra in doubles on Saturday. Reverse singles are set for Sunday.
Argentina, which will be without top player Juan Martin del Potro, has lost all five previous matches against France.