In-form Novak Djokovic will have the chance to regroup before his French Open third-round match reconvenes on Saturday after losing the second set against Argentine Juan Martin Del Potro.
The contest, already switched to Court Suzanne Lenglen after other matches ran over, was suspended for bad light on Friday at 6-3 3-6 with former U.S. Open champion Del Potro testing the Serb for the first time in the clay grand slam.
World number two Djokovic has won 39 matches in a row since the start of the year and is bidding for his first Roland Garros title.
Del Potro, who has been dogged by injuries and arrived as the 25th seed despite his 2009 success at Flushing Meadows, had a break point in the first game but Djokovic held with a superb forehand before breaking for 3-1 when the Argentine netted.
A Djokovic double-fault let his opponent back in during the second set, however, and Saturday promises to be an enthralling finish.