Britain's Andy Murray was leading American John Isner in their fourth-round match when rain brought a halt to play at the French Open in Paris.
The second seed saved three set points in a 16-minute first-set tie-break and was leading 7-6 (11-9) 2-1 when play was suspended at 16:00 BST.
Officials hope the rain will clear later to enable the match to resume.
Japanese fifth seed Kei Nishikori was 4-2 up on France's Richard Gasquet on Court Philippe Chatrier.
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