 Then, he returned to Argentina to play for his first club Gimnasia y Esgrima de La Plata, which was struggling to keep its Primera A standing.Even though Sosa had a mediocre 2008/09 season, scoring only 2 goals in 24 games, he helped Gimnasia to avoid relegation.Perhaps, his most memorable moment during his last return to Gimnasia happened on 5 April 2009.