British number one Johanna Konta suffered a shock defeat by world number 109 Hsieh Su-wei in the first round of the French Open.
Seventh seed Konta dominated the first set but eventually went down 1-6 7-6 (7-2) 6-4 to Taiwanese Hsieh.
Konta, 26, has yet to win a match in the main draw at Roland Garros after three successive first-round losses.
She will now head back to the UK and hope for more success in the grass-court season.
Konta, who is ranked eighth in the world, has also lost twice in qualifying in her five visits to Roland Garros.
Her day was summed up by the final game, in which she missed four chances to break back and stay in the match, one through some Hsieh brilliance and another thanks to the cruellest of net cords.
“I think I definitely created some opportunities; I think I didn’t do well enough in necessarily converting them,” said Konta.
“But then there were times where I felt that she did play incredibly well.”
The Taiwanese player clinched a remarkable win when Konta’s return found the net after two hours and 15 minutes.
Konta’s exit means there are no British women left in the singles draw at Roland Garros, while Andy Murray and Kyle Edmund play in the men’s draw later on Tuesday.
Ragged display costs Konta
Konta’s record on clay might be modest at best – just four wins at WTA main draw level in her career – but she is now established in the world’s top 10 and among the title contenders when the Grand Slams come around.
Roland Garros remains the least likely venue for Konta to make that breakthrough, but defeat by such a lowly ranked player with an enticing-looking draw will be a huge disappointment.
She dominated the early exchanges, winning 11 of the first 12 points, and was rock solid on serve for the first set and a half.
A comfortable victory looked likely but Hsieh finally began to land some first serves and started to move Konta out wide with her unorthodox forehand slice.
Both players had ample chances in the second set, Hsieh missing four break points in game seven – the second with a woeful smash into the net – before Konta failed to capitalise from 0-40.
The Briton began the tie-break well but missed a makeable smash at 2-2, and Hsieh took control, scrambling superbly to wrest control of the rallies.
Konta now faced a real test, the early certainty on her groundstrokes long gone and Hsieh now making far more returns.
Having made it through two sets without dropping serve, Konta was broken twice in succession in the third, and the unflappable attitude that has marked her recent rise began to fray at the edges.
There were shakes of the head and pleading looks towards Belgian coach Wim Fissette as she continued to make errors.
A dramatic final game saw more chances come and go but it was a 38th error of what became a ragged display that finally ended Konta’s clay-court season for another year.
“My expectations are never results-orientated,” added Konta.
“In that sense, whether I’ve lost first round or third round or quarters, I do my best to not judge myself on that aspect.
“Obviously, I like to be involved in a tournament for as long as possible, and I would have liked to have been involved here longer.”
“Konta said before the French Open that she has really enjoyed the clay court season and the challenges it has presented her both professionally and personally. This, though, was a chastening experience.
“Hsieh played extremely well. She is an unorthodox player with a double handed forehand who uses plenty of slice and variety. Her defence was magnificent but Konta had little answer in the deciding set as the unforced errors mounted up.
“The world number eight has entered grass court events in Nottingham, Birmingham and Eastbourne in the run up to Wimbledon, and will be hoping a change of surface sees the return of the commanding player on display in the first three months of the season.”
Jill Craybas, former world number 39, on BBC Radio 5 live sports extra:
“What a match. And what a good effort from Hsieh to come back after losing the first set so easily.
“Johanna Konta came out at the start and played very well, she was trying to do the right things but I think you have to give credit to Hsieh.
“I don’t think Konta played that bad, Hsieh just lifted her level and brought in more variety.
“Konta made a few mistakes in the third set and they came because she didn’t trust her movement on the clay.
“She is still striking the ball well and, with her demeanour and attitude, she will get better on the clay.
“This defeat won’t have an adverse effect on her grass-court season. It is completely different.”