Hernandez missed the 39-22 defeat by France last weekend because of a thigh strain, but has been passed fit for the final match of the Pumas' year.
The Racing Metro star, who can also play fly-half, replaces Lucas Gonzalez Amorosino with Nicolas Sanchez selected in the number 10 jersey.
Exeter wing Gonzalo Camacho and Montpellier centre Santiago Fernandez come in for Horacio Agulla and Gonzalo Tiesi with Marcelo Bosch shifting to outside centre.
Montpellier tighthead Maximiliano Bustos makes he debut at the expense of Juan Figallo.
Argentina: J M Hernandez (Racing Metro), G Camacho (Exeter), M Bosch (Biarritz), S Fernandez (Montpellier), J Imhoff (Racing Metro), N Sanchez (Bordeaux-Begles), M Landajo (San Isidro), M Ayerza (Leicester), E Guinazu (Southern Kings), M Bustos (Montpellier), M Carizza (Racing Metro), J F Cabello (Tucuman), J M Fernandez Lobbe (Toulon, capitan), J M Leguizamon (Lyon), L Senatore (Gimnasia Rosario).
Replacements: A Ceevy (Montpellier), N Lobo (Montpellier), F Gomez Kodela (Biarritz), T Vallejos Cinalli (Scarlets), T Leonardi (San Isidro), N Vergallo (Tolouse), G Tiesi (San Isidro), M Montero (Pucura).
Gilbert has released a new line of rugby cleats. The Gilbert Virtuo 8S is part of the exciting new product. Check it out.
The entire All Blacks apparel line has been updated for 2013/14. Check out the New Zealand All Blacks polo.
The Nike Tiempo is a solid rugby cleat and one of few styles still made from full-grain natural leather.
The Gilbert Blitz 8S rugby cleat is a great cleat at a great price of $69.99. Get a new pair of cleats today.
A cool looking all black rugby cleat with the high performance adidas is known for. Get in the Gear!
Wear the crest of the British and Irish Lions on your t-shirt. A great look for the summer.
The All Blacks Performance t-shirt is black with hints of blue from the training jersey. Very Cool.
The New Zealand All Blacks training jersey for 2013/14. Get in the Gear!
The USA Rugby Pro Alternate rugby jersey is perfect for any fan of the Eagles. Get yours to wear during the summer Test matches.
The NEW All Blacks 2013/14 jersey has arrived at World Rugby Shop. Dare to wear the colors of the All Blacks.