Marseille - Defending champion Juan Martin del Potro beat Michael Llodra 3-6, 7-6 (4), 7-5 to reach the Open 13 quarter-finals on Thursday.
Del Potro hit 14 aces and saved nine of the 10 break points he faced as he was pushed all the way by the veteran Frenchman in a rematch of last year's final.
"It was very, very tough. It shows the level of the tournament is so high," del Potro said. "I think I played a very good level at the end of the match. He played well throughout the match. I needed luck to beat him on Thursday, because he deserved to win the match as well."
The 2009 US Open champion faces another Frenchman, Gilles Simon, in the last eight after he advanced to his third straight quarter-finals with a 6-3, 6-1 win against Roberto Bautista-Agut, although Simon's serve was again not at its best. He broke his Spanish opponent seven times, but conceded three breaks of his own.
Meanwhile, Russian qualifier Dmitry Tursunov also advanced after he upset fourth-seeded Janko Tipsarevic 7-6 (4), 6-2.
Tursunov, a semi-finalist at the tournament two years ago, saved the four break points he faced and twice broke the Serb. He next plays Gilles Muller of Luxembourg.
Seventh-seeded Jerzy Janowicz of Poland beat Frenchman Julien Benneteau 7-6 (0), 6-3, setting up a quarter-final with top-seeded Tomas Berdych of the Czech Republic.