Katie Boulter was forced to retire due to injury during her match against Hungary's Anna Bondar in the last-16 of the Lyon Open.
The British No 4 had been trailing 6-3 to Bondar when she withdrew after suffering what appeared to be an injury to her left leg.
It brought a halt to an impressive run of form that had seen her reel off eight straight wins, including victory over Anna Blinkova in the final in Grenoble to end her four-year wait for a WTA singles title.
Elsewhere second-seeded Sorana Cirstea progressed with a 6-3 7-5 win over Stefanie Voegele of Switzerland to set up a quarter-final meeting with Bondar.
No 3 seed Viktorija Golubic meanwhile overcame Mai Hontama of Japan 1-6 6-4 6-4 and is now due to face Russia's Vitalia Diatchenk, who beat Anna-Lena Friedsam of Germany 6-3 2-6 6-4.
Alison Van Uytvanck joins them in the next round after her 6-2 6-4 win over Russia's Varvara Gracheva.
Britain's Heather Watson is in action in the Monterrey Open on Thursday when she takes on Spanish eighth seed Nuria Parrizas Diaz.
Fernandez wins in Monterrey
Canadian teenager Leylah Fernandez rescued five of six break points on her way towards a 6-1 4-6 7-6(3) victory over China's Qinwen Zheng in Monterrey, Mexico.
The 19-year-old, who is currently ranked 21st in the world, will now meet either Wang Qiang of China or Mayer Sherif of Egypt in the next round after what was her first tournament appearance since her first round defeat in the Australian Open.
Spain's Sara Sorribes Tormo beat France's Harmony Tan 6-2 6-2, Camila Osorio overcame Marcela Zacarías 7-6(2) 6-3 and Hadda Maia coasted to a 6-2 6-2 win over Wang Xinyu.