Paris, France, 25 May 2017 | AAP

Nick Kyrgios’s untimely injury setback has cost the Australian No.1 an all-important top-16 seeding for the French Open starting on Sunday.

After a blinding hardcourt campaign in the United States, Kyrgios’s momentum stalled when the death of his grandfather limited claycourt exposure and then a hip flexor problem forced his withdrawal from last week’s Rome Masters.

As a result, Kyrgios has dropped to 19th in the rankings and has been seeded 18th for Roland Garros after rising one position due to Roger Federer’s scratching to focus on Wimbledon.

Kyrgios could now run into a higher-ranked rival as early as the third round where he’s been bundled out in both the past two years.

Australia’s top two women – world No.24 Sam Stosur and the 25th-ranked Daria Gavrilova – will also be sweating on Friday night’s draw in Paris.

The absence of pregnant world No.2 and reigning Australian Open champion Serena Williams has elevated the Aussie duo one spot each with Gavrilova seeded in Paris for the first time following her run to last week’s quarterfinals in Rome.

Kyrgios will enter the second slam of the year having contested just five claycourt matches in a rough build-up.

But after a shock three-set loss to Argentine qualifier Nicolas Kicker in his opening match this week in Lyon, the 22-year-old put his sore hip through three sets of doubles on Wednesday with countryman Matt Reid.

While Kyrgios and Reid progressed to the semi-finals with a 7-6(4) 3-6 [11-9] win over fourth seeds Brian Baker and Nikola Metkic, fellow Australians Bernard Tomic, Thanasi Kokkinakis and teenage wildcard Alex Di Minaur all hit the red dirt at Roland Garros for hearty practice sessions.

Davis Cup player Jordan Thompson is also in the draw but 20-year-old Marc Polmans was unable to join his Aussie countrymen after falling 6-3 6-7(6) 6-4 to Argentine Guido Pella in the second round of qualifying.