The following season, Gargano made his UEFA Cup debut in a 3–2 win over Benfica in the first round. However, in the second leg, Benfica would win 2–0, eliminating Napoli. On 29 September 2008, he provided a winning goal for Germán Denis, scoring the only goal in the game against Bologna. In the mid second season, he suffered a fractured foot during training in March 2009 and was sidelined for two months. He recovered in time to feature in the last two games of the Serie A season, against Catania and Chievo.