Italian fourth seed Jannik Sinner has withdrawn from the Paris Masters with fatigue.
Sinner beat American Mckenzie McDonald in the second round but did not start play until after midnight and finished at 02:37 local time on Thursday.
The 22-year-old was scheduled to play Australian Alex de Minaur in the third round later on Thursday.
Meanwhile, world number one Novak Djokovic laboured to a 4-6 7-6 (7-2) 6-4 win over Dutchman Tallon Griekspoor.
The Serb looked out of sorts and had to come from behind to grind out the victory but will face German Daniel Altmaier or Danish sixth seed Holger Rune, who play in the late match, in the quarter-final.