Contepomi, 35, who has retired from European club rugby as he winds down his career, will be making his debut in the elite southern hemisphere tournament that also includes Australia and New Zealand.
He led the Pumas in their 2-0 home series loss to England in June.
There are also tournament debuts for forwards Matias Diaz and Pablo Matera, both promoted from the under-20 Pumitas in the side named on Tuesday by coach Santiago Phelan.
Diaz lines up in the front row in place of Marcos Ayerza, who pulled out at the weekend with cartilage damage, while Matera is at blind side flanker due to Fernandez Lobbe failing a fitness test on a calf injury.
Juan Martin Hernandez, flyhalf in Argentina's debut championship last year, has relinquished his place to Nicolas Sanchez and lines up at fullback, the position where he made his name with Stade Francais.
Team: 15-Juan Martin Hernandez, 14-Gonzalo Camacho, 13-Marcelo Bosch, 12-Felipe Contepomi (captain), 11-Juan Imhoff, 10-Nicolas Sanchez, 9-Martin Landajo; 8-Leonardo Senatore, 7-Juan Manuel Leguizamon, 6-Pablo Matera, 5-Patricio Albacete, 4-Manuel Carizza, 3-Matias Diaz, 2-Eusebio Guinazu, 1-Juan Figallo
Replacements: 16-Agustin Creevy, 17-Nahuel Lobo, 18-Juan Pablo Orlandi, 19-Mariano Galarza, 20-Julio Farias Cabello, 21-Tomas Cubelli, 22-Santiago Fernandez, 23-Horacio Agulla
- Sports & Recreation