Tursunov defeated Gasquet, 3-6, 6-3, 6-4, and moved into the tournament quarterfinals in one of four matches that sent seeded players packing.
Fifth-seeded Carlos Moya was beaten, 6-3, 6-4, by Agustin Calleri; sixth-seeded and hometown favorite Lleyton Hewitt, was taken out by wild-card entrant Chris Guccione, 7-6 (7-4), 7-6 (7-2); and No. 8-seeded Fernando Verdasco dropped a 6-3, 6-4 decision to Sebastien Grosjean.
Fourth-seeded Tomas Berdych escaped the upset bug with a, 7-6 (7-3), 6-2, win over Gilles Simon. Also on Wednesday, Fabrice Santoro swept by Steve Darcis, 6-1, 6-3; Radek Stepanek stopped Andreas Seppi, 7-5, 2-6, 6-4; and Evgeny Korolev beat Ivo Minar, 6-2, 6-3.
Thursday's quarterfinals pairings have Tursunov playing Grosjean, Berdych meeting Guccione, Stepanek versus Calleri and Santoro against Korolev.
Celebrity Couples of 2014 [PHOTOS]