Marseille - Russian qualifier Dmitry Tursunov upset fourth-seeded Janko Tipsarevic 7-6 (7/4), 6-2 to reach the Open 13 quarter-finals on Thursday.
The 30-year-old Tursunov, a semi-finalist at the tournament two years ago, saved the four break-points he faced and twice broke the Serb.
Sixth-seeded Gilles Simon of France advanced to his third straight quarter-final with a 6-3, 6-1 win against Roberto Bautista-Agut, although Simon's serve was again not at its best. Although he broke his Spanish opponent seven times, he conceded three breaks of his own.
Simon faces either No 2-seed Juan Martin del Potro of Argentina, the defending champion, or countryman Michael Llodra in the last eight, while Tursunov plays Gilles Muller of Luxembourg.