China's Li Na won her rematch with Slovakia's Dominika Cibulkova in the quarter-finals of the BNP Paribas Open at Indian Wells, California on Thursday.
Ukrainian giantkiller Alexandr Dolgopolov also continued his fairytale run in the desert, blunting the booming serve of Canadian Milos Raonic to book his place in the last four of the men's event.
In a tournament that has been packed with surprises and high-profile casualties, the 32-year-old Li has been a model of consistency, ferociously battling through each round.
In her first meeting with the talented Cibulkova since she beat the Slovak in the Australian Open final in January, Li once again proved too strong, winning 6-3 4-6 6-3 in a little over two and a half hours.
Li next meets American Sloane Stephens or Flavia Pennetta of Italy.
The Chinese, the top seed in the absence of world number one Serena Williams, has struggled with her serve all week and committed eight double faults against Cilbukova, four in the opening set and four more in the third when the pressure was on.
The Slovak also made eight doubles while the pair combined for more than 100 unforced errors.
Li got the decisive break late in the third set and then served out for victory to stay on course for her first title at one of the biggest events outside the grand slams.
Dolgopolov has been a revelation at Indian Wells. He was thrust into the spotlight when he scored an upset win over world number one Rafa Nadal in the third round.
Players who register shock wins often fail to maintain their form on but the 28th seed has gone from strength to strength, beating three seeds in succession.
Raonic, the 10th seed and one of the biggest servers in tennis, beat Wimbledon champion Andy Murray on Wednesday but he found Dolgopolov too hot to hold, the Ukrainian winning 6-3 6-4 in less than 80 minutes.
Not only did Dolgopolov succeed in breaking the Canadian's serve three times, including twice in the second set to overcome a 3-0 deficit, but he showed that he also has a serve to be reckoned with as he fired six aces, two more than his opponent.
Dolgopolov next faces four-times champion Roger Federer or in-form South African Kevin Anderson.
(Reporting by Julian Linden in New York, editing by Alan Baldwin and Tony Jimenez)