Juan Martin Hernandez has been selected at fly-half for Argentina for their World Cup opener against hosts France in Paris on Friday.
The 25-year-old Stade Francais star is a full-back by trade but has expressed a desire to play at number 10.
Pumas coach Marcelo Loffreda has chosen Hernandez for the position ahead of Felipe Contepomi and Federico Todeschini.
Contepomi moves into the centres, where he will partner his twin brother Manuel, while Todeschini – an expert place-kicker – is on the bench.
Regular number eight Gonzalo Longo is sidelined with a leg injury so Lucas Ostiglia is named at the back of the scrum.
Juan Martin Scelzo, Ignacio Corleto and Juan Manuel Leguizamon have all shrugged off minor knocks and will start.
But lock Rimas Alvarez is named on the bench, with Loffreda sticking with the second-row combination of Ignacio Fernandez Lobbe and Patricio Albacete.
The team is captained by veteran scrum-half Agustin Pichot.
Argentina side for Friday’s Pool D clash against France:
I Corleto; L Borges, M Contepomi, F Contepomi, H Agulla; JM Hernandez, A Pichot (capt); R Roncero; M Ledesma, JM Scelzo, I Fernandez Lobbe, P Albacete, J Fernandez Lobbe, JM Leguizamon, L Ostiglia.
Replacements: AV Basualdo, S Gonzalez Bonorino, R Alvarez, M Durand, N Fernandez Miranda, F Todeschini, H Senillosa.