China's Peng Shuai used a minimal amount of clay court preparation on Tuesday to knock French top seed Marion Bartoli out in the first round of the Portugal Open 6-0, 1-6, 6-4.
Peng, a 2010 semi-finalist in her only previous appearance at the event, had just limited time to train after returning to her homeland to treat a shoulder injury following a Miami second-round loss in March.
After receiving treatment in her hometown of Tianjin, she travelled on to Germany where her meagre clay preparation proved just the ticket to stunning Bartoli, the world number 14 who has now lost her last four WTA matches dating to mid-March.
"I"m very happy to win in such windy conditions," said the 27-year-old Peng, ranked 34th and second Chinese behind Li Na.
"We both started to play quite well, but at 3-3 when I had 40-15 she hit quite a lucky return and that really hurt me"
"The clay was blowing around a lot, making it even more difficult."
Pen won in an hour and three-quarters as the erratic Bartoli produced eight double-faults and lost serve five times.
The quirky French player has reunited with her doctor father Walter as coach after several months of unsuccessful trials with other potential mentors including former Wimbledon champion Jana Novotna, but is still looking for a win.
"The first match on clay is always tough for me," said Bartoli.
"I had a lot of trouble finding my game and my feet on the court.
"She was playing extremely well. I just tried my hardest and was able to play some good shots in the second set. I felt like the third was really close.
"We both started to play quite well, but at 3-3 when I had 40-15 she hit quite a lucky return and that really hurt me.
"It was a very difficult draw, but I think it is better for me to have those kind of matches early in the clay court season and try to improve for the big events coming up."
Elsewhere in the opening round, Galina Voskoboeva of Kazakhstan beat Swede Sofia Arvidsson 6-3, 6-4 to next face two-time grand slam winner and wild card entry Svetlana Kuznetsova.
Wimbledon quarter-finalist Tamira Paszek has now gone winless for three months since the Australian Open, with the 31st-ranked Austrian losing her seventh straight match as she went down 6-1, 6-3 to Romanian Monica Niculescu.