Gallery: Contador, Boonen roll out for Tour de San Luis

Some of the biggest stars in cycling will be presented for the 6th Tour de San Luis in Argentina today, with Saxo Bank's Alberto Contador, Tom Boonen and Levi Leipheimer of Omega Pharma-Quickstep and Vincenzo Nibali (Liquigas-Cannondale) amongst the starters for the UCI 2.1 race.