Garbine Muguruza's challenge at the Wuhan Open is over following a quarter-final defeat to Jelena Ostapenko, although her number-one ranking is safe thanks to Karolina Pliskova's elimination earlier in the day.
Top seed Muguruza made a strong start against the French Open champion, but ultimately fell to a 1-6 6-3 6-2 defeat - a first for the Latvian against her Spanish opponent.
Pliskova had earlier been beaten by Australia's Ashleigh Barty, who came from a set down to win 4-6 7-6 (7-3) 7-6 (7-2) and claim her maiden triumph over a top-five player, leaving Ostapenko as the only seed in the last four.
Ostapenko and Barty will meet each other for a place in the final, while the other semi sees Caroline Garcia take on qualifier Maria Sakkari, who maintained her impressive run on Thursday with victory over Alize Cornet.
Garcia, meanwhile, is into her first Premier 5 semi-final thanks to a win against Ekaterina Makarova.
ONE AND DONE FOR MUGURUZA
Muguruza's number-one ranking was on the line this week and, while Pliskova would have needed to win the tournament to topple the Wimbledon champion, it will doubtless have been on her mind in Wuhan.
Defeat for Pliskova secured Muguruza's place at the rankings summit for the time being, but she swiftly lost her place in this tournament at the hands of Ostapenko.
The 20-year-old reeled off six games in a row in the deciding set to wrap up the win.
"It was a pretty close match at the end," said Muguruza. "It was three sets and it was tight. I think she's just playing very good with a lot of confidence."
BARTY COMES TO THE PARTY
Barty has gone from strength to strength this week, beating Johanna Konta and Agnieszka Radwanska before toppling Pliskova.
Pliskova came within two points of winning the match and saved three match points when Barty had the chance to serve out the match, but lost the decisive tie-break.
After starting 2017 outside the top 200, Barty will be inside the top 30 for the first time in her career next week.
"It's been an amazing season, it really has," said the 21-year-old. "I was very motivated and worked very hard last year to get back to where we are now."
MORE SAKKARI TORMENT FOR CORNET
Cornet lost to Sakkari in the second round of the Australian Open this year and there was a repeat performance from the unheralded Greek in Wuhan.
The Athens-born world number 80 had already claimed the scalp of Caroline Wozniacki and Elena Vesnina and Cornet was unable to halt her charge.
Sakkari will be looking to see off another French opponent in the form of Garcia in the last four after battling from 2-0 down to take the first set and overcoming a 3-1 deficit in the second to send Cornet packing.