Andy Murray was digging deep to avoid a shock first-round loss to veteran Radek Stepanek when their French Open match was suspended because of bad light.
World number two Murray, who beat Novak Djokovic to win the Italian Open in his last match, lost the first two sets to the 37-year-old Czech qualifier.
The Briton won the third set and was leading 4-2 in the fourth when the duo were called off at 20:22 BST, with Stepanek leading 6-3 6-3 0-6 2-4.
The match resumes at 11:30 on Tuesday.
- Murray has not lost in the first round of a Grand Slam tournament since the 2008 Australian Open
- Murray has recovered to win from two sets down eight times in his career
It was after 18:00 when the players took to the court following a lengthy rain delay, and from the start Murray was on the back foot.
The 29-year-old lost his serve in third game of the first set and was broken again in the ninth as Stepanek, the oldest player in the draw, drew upon his vast experience.
The second seed broke to love to start the second set but then immediately lost his own serve and Stepanek, ranked 127 in the world, broke again at 4-3 to carve out a two-set lead.
Murray, though, showed his resolve and raced through the third set in just 18 minutes as former world number eight Stepanek began to lose his way in the fading light.
Stepanek, a Wimbledon quarter-finalist in 2006, seemed to be stalling for time and received a warning after taking a toilet break and then changing his shirt.
It did not disrupt Murray’s rhythm and the Scot extended his run of games to nine before the Czech held his serve.
The British number one was next to serve and seemed well placed to force a decider when play was called off for the evening.
Murray is bidding to join fellow Britons Kyle Edmund and Heather Watson in the second round, while compatriots Johanna Konta, Laura Robson and Aljaz Bedene are due to start their campaigns on Tuesday.
BBC tennis correspondent Russell Fuller:
“Lacking timing – and looking a shadow of the player who had produced such dominant tennis in Rome two weeks ago – Murray found himself two sets down to Stepanek in no time at all.
“The 37-year-old, with three qualifying wins under his belt, adapted to the slow conditions superbly, and only by winning 10 of the last 12 games of the night did Murray drag himself back into the match.
“The world number two will have to start so much better on the resumption, as after a good night’s sleep and with nothing to lose, the Czech still poses a serious threat.”
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