Argentina captain Juan Martin Fernandez Lobbe has been ruled out of the Dove Men Series clash with Wales on November 16.
The 31-year-old flanker fractured his elbow during Toulon's Top14 defeat to Toulouse on Saturday and is set to be sidelined for up to three months.
"Against Toulouse on Saturday flanker Juan Martin Fernandez Lobbe suffered a fracture of the right elbow," read a Toulon statement.
"He will consult a Marseille professor for surgery. It is estimated he will be unavailable for two to three months."
Argentina also face England, Italy and Ireland during their European tour.
Meanwhile former Wales head coach Sir Graham Henry has left his role as technical advisor to Los Pumas.
The World Cup winning-coach has stepped down to focus on a similar role with Super Rugby side the Blues.
He is just the latest departure from the Pumas' coaching staff after Santiago Phelan quit his role in charge. Phelan had been at the helm for six years but will be replaced by Argentina B coach Daniel Hourcade.
As the countdown continues for RWC2015, Tournament Chief Executive Debbie Jevans visited the Millennium Stadium to discuss preparations for the eight matches and reveal the positive news that 100,000 tickets for games at the home of Welsh rugby have sold in the last seven days.
Jason Harries is targeting a first win on the World Series circuit this season with Wales. The series returns to action this weekend in Dubai where Harries is part of a team hoping to build from its efforts in round one in October.
Wales skipper Jevon Groves says his side have addressed a few points from Gold Coast and aim to 'hit the ground running' in the next two rounds of the World Series, kicking off with this weekend in Dubai before heading off to South Africa next week.
Wales Sevens manager Steff Thomas is hopeful his side can build from a quarter-final spot in the opening round of the World Series in Australia when his side take part in the forthcoming double header in Dubai and South Africa.