Rome, August 19 - Italy striker Pablo Daniel Osvaldo has joined Premier League club Southampton from AS Roma. The Argentine-Italian signed a four-year, 15-million-euro contract, a record for the southern English club. Osvaldo, who played under Southampton boss Mauricio Pochettino at Espanyol, has won nine caps for Italy. He joined Roma in 2011 and scored 16 goals in Serie A last season. His previous clubs include Atalanta, Lecce, Fiorentina and Bologna.