"We have asked this team to maintain the high standards set last week, add an extra dimension to their play, and prove they are capable of beating this Argentinean team." said Wales coach Gareth Jenkins.
Wales have never lost a full Test series in Argentina. A 2-0 series win for Graham Henry's Wales in 1999 was the first time a British or Irish side had won a series in the country.
The two-Test series between the countries in 2004 was shared as Wales recovered from a first Test defeat to win the second in Buenos Aires
Wales: L Byrne (Ospreys); M Jones (Scarlets), J Robinson (Blues), J Hook (Ospreys), S Williams (Ospreys); N Robinson (Blues), M Phillips (Blues); D Jones (Ospreys, capt), H Bennett (Ospreys), A Jones (Ospreys), I Evans (Ospreys), I Gough (Dragons), A Wyn Jones (Ospreys), G Thomas (Scarlets), A Popham (Scarlets).
Replacements: M Watkins (Scarlets), N Brew (Dragons), A Williams (Bath), J Yapp (Blues), R Thomas (Dragons), R Hibbard (Ospreys), G Delve (Bath).
Referee: Dave Pearson (England)