Roger Federer and Gael Monfils were tied at one set all when their French Open fourth-round match was suspended for bad light.
The pair had walked onto Court Philippe Chatrier at 19:13 local time after a day of rain interruptions.
Switzerland's Federer won the first set 6-3 in 29 minutes, but Frenchman Monfils retaliated to take the second 6-4.
They will resume in Monday's second match on Chatrier at around 12:00 BST.
The winner will face Swiss number two and eighth seed Stan Wawrinka, who saw off France's Gilles Simon 6-1 6-4 6-2 on Court Suzanne Lenglen.