Roddick out of French Open
Acasuso, who is ranked 69th in the world and has won just two titles in his career, defeated the 22-year-old American 3-6, 4-6, 6-4, 6-3, 8-6 in three hours and 21 minutes.
World number three Amelie Mauresmo is relishing the prospect of a real fight in her next match against Ana Ivanovic after cruising past compatriot and wild-card Alize Cornet in the second round.