“Due to weather, there will be no matches played at #RG16 today,” said the Roland Garros Twitter feed.
There could be more problems on Tuesday with further rain forecast throughout the day before conditions brighten on Wednesday. Eight last-16 matches planned for Monday plus two more which had already been held over from Sunday night will now be played on Tuesday.
Three quarter-finals are also due to take place Tuesday -- Andy Murray against Richard Gasquet and defending champion Stan Wawrinka in the men’s event while Shelby Rogers was to face Garbine Muguruza in the women’s singles.
Play had been set to get underway at 1100 (0900GMT) on Monday but was eventually called off just before 1400 (1200GMT).
“All cancelled for today -- rain, rain go away,” tweeted Czech seventh seed Tomas Berdych who was due to face former runner-up David Ferrer of Spain for a last-eight spot.