Ashleigh Barty's preparations for the French Open were hampered on Friday when she was forced to pull out of the Internationaux de Strasbourg due to injury.

The Australian - who is seeded 17th for the upcoming grand slam at Roland Garros - was trailing in her semi-final against Anastasia Pavlyuchenkova when she opted to withdraw after 41 minutes on court.

"It was a tough decision for me," Barty, who did not make clear the exact problem, told the WTA Tour's website. "It's never easy withdrawing from a tournament."

"I'm disappointed not to be able to play my best and to finish the match today, but I think at this stage I have to listen to my body, and today I was unable to play at 100 percent."

"That's not fair to my opponent or the tournament, to be out there and not be able to give my best effort."

Pavlyuchenkova was leading 6-4 1-0 when the match was halted, sending the Russian through to her first final in 2018.

She will face Dominika Cibulkova, who rallied from a set down to beat fourth seed Mihaela Buzarnescu 2-6 7-6 (7-5) 6-1, on Saturday for the title.

Meanwhile, at the Nuremberg Cup in Germany, 13 turned out to be an unlucky number for Kiki Bertens as she saw her unbeaten run in the event come to an end.

The third seed suffered defeat in her delayed quarter-final against the unseeded Kirsten Flipkens - who then later lost 6-3 6-1 to Alison Riske in the last four as organisers made up for the time lost to rain earlier in the week.

Johanna Larsson progressed from the other side of the draw, the Swede reaching her first WTA Tour final in three years thanks to a 4-6 6-3 6-1 triumph over Katerina Siniakova.