Daniil Medvedev succumbed to second-round defeat against Stan Wawrinka at the Moselle Open on Thursday, while Hubert Hurkacz coasted past Dominic Thiem.
World number four Medvedev fell to a 6-4 6-7 (7-9) 6-3 loss against three-time major winner Wawrinka, who will next meet Mikael Ymer after his straight-sets win over home favourite Gregoire Barrere.
Second seed Hurkacz did not experience such struggles against Thiem as the Pole cruised to a 6-3 6-4 as he served 12 aces in a dominant performance in Metz.
Hurkacz will face Arthur Rinderknech in the next round after the Frenchman battled to a 7-6 (13-11) 6-3 triumph over fifth seed Nikoloz Basilashvili.
Alexander Bublik, the seventh favourite in France, was also made to work for his progress to the quarter-finals, downing Emil Ruusuvuori 6-7 (4-7) 6-4 6-3.
Fourth seed Holger Rune awaits Bublik after Benjamin Bonzi retired due to injury when 6-4 4-1 down against the Dane.
Lorenzo Sonego coasted through his second-round clash to defeat Gilles Simon 7-6 (7-2) 6-4 to tee up a last-eight clash with Sebastian Korda.