Twenty-six-year-old Czech Kvitova, twice the Wimbledon champion, struggled to a 6-2, 4-6, 7-5 victory over Danka Kovinic.

Montenegro's Kovinic has never made it past round two at a Grand Slam but the 21-year-old made life difficult for the 10th seed.

Kvitova, though, will count herself fortunate to be safely through as several matches remain uncompleted after showers forced an early cancellation of the day shortly before 7pm at Roland Garos.

With no roof at the Paris venue, other games failed to get started entirely with players now facing congested schedules.

Eleventh-seed Lucie Safarova, another Czech, is safely through in the women's draw after a straightforward 6-2, 6-0 win over Russia's Vitalia Diatchenko.

Another Russian, 13th seed Svetlana Kuznetsova, was one player to be frustrated by the rain with her match against Kazahkstan's Yaroslava Shvedova suspended.

Shevedova took the opener 6-4 before Kuznetsova levelled by winning the second 6-1.

In the final set, the Russian is 3-1 ahead.

Australian Nick Kyrgios is one player to progress from the first round in the men's draw after he ousted Marco Cecchinato of Italy in straight sets.

Kyrgios, who has been warned that his poor behaviour could see him banned from Australia's Rio 2016 Olympic team, came through 7-6, 7-6, 6-4.

Home favourite Benoit Paire, the 19th seed, completed an epic contest against Moldovan qualifier Radu Albot, eventually triumphing 6–2, 4–6, 6–4, 1–6, 6–4.

Japan's Kei Nishikori, the fifth seed, will have to resume tomorrow against Simone Bolelli.

The quarter-finalist from 2015 leads the Italian 6-1, 7-5, 2-1.

American Jack Sock and Dutchman Robin Haase are locked at two sets all and will have to return for their decider.

Sock went 6-3, 7-5 up before Haase replied by winning the next two sets 6-3, 7-6.