With the European clay-court swing now well underway, the 8 players left in the field at the TEB BNP Paribas Tennis Championships Istanbul has been decided, led by top seed Elise Mertens, who was pushed to 3 sets on Thursday by Viktorija Golubic.
Also through to the last 8 are Veronika Kudermetova, Ana Bogdan, and Fiona Ferro, joining Katerina Siniakova, Ana Konjuh, Marta Kostyuk and and Sorana Cristea who played on Wednesday.
It took Mertens 2 hours 16 minutes to find an answer to the Swiss challenge, the Belgian delivering 9 aces against her 5 double-faults and winning 72 percent of her first serves and 48 percent on her second.
After two evenly-balanced sets, Mertens dominated the third to notch up a 6-4 4-6 6-1 win to charge into the quarters where will face Siniakova from the Czech Republic on Friday.
Mertens will be the favourite heading into this match, with the top-seed having made a fine start to her season, posting a 15-4 record so far in 2021.
Although the Czech has lost all 3 of their previous meetings, she has demonstrated her prowess on the clay with wins over Cristina Bucsa and Kristina Mladenovic so far this week.
Meanwhile, 3rd-seeded Kudermetova from Russia came through in straight sets against the Estonia’s tricky Kaija Kanepi, 6-4 6-3, to set up a meeting with Romania’s Ana Bogdan.
Kudermetova is making strides this season, arriving in Istanbul on the back of some solid results, including capturing the title in Charleston, and making it to the final in Abu Dhabi.
The Russian has been fairly consistent throughout 2021, holding a strong 18-8 win-loss record for the year.
Against a relatively unheralded opponent like Bogdan, Kudermetova will be sensing an opportunity to make it to yet another semi-final.
Bogdan, too, has impressed at the WTA Istanbul Cup, beating Nao Hibino and then upsetting Czech Barbora Krejcikova, both in straight sets so there is little danger of Kudermetova underestimating the Romanian, thanks to their history.
The 28-year-old Romanian’s excellent court-coverage makes her a hard player to beat and she is more than capable of turning defence into attack even when on the stretch.
On Thursday Bogdan needed a little over an hour and 20 minutes to close out a 6-3 6-3 win over the Czech No 5 seed, and advanced to the quarter-finals.
Bogdan leads Kudermetova in the head-to-head with a comfortable 3-0 margin and despite the gap in their rankings, this one could well have a close finish and while the Romanian certainly has the odds stacked against her, she knows her opponent’s game well, and has managed to dismantle it in the past.
Elsewhere, Fiona Ferro from France defeated Russian veteran Vera Zvonareva, 6-3 6-3, and will take on another Romanian, Sorana Cirstea, on Friday in what is an important match for both women.
Ferro made her breakthrough last season when she won her first WTA title in Palermo and then reached the 4th round at the French Open, all on clay, but injuries have hampered her progress since and this season has been broadly disappointing for the Frenchwoman.
Nevertheless she made an excellent start to her week by dismissing 2nd seed Petra Martic in straight sets before beating Zvonareva in straight sets to reach the last eight.
Cirstea picked up battling straight-sets wins over Katerina Kozlova and then Anastasia Potapova on Wednesday in Istanbul.
The Romanian also won this pair’s only previous meeting which came in 2017 at this very event, but Ferro has improved considerably in the intervening 4 years and is now the higher-ranked of the two.
The last quarter-final is between Konjuh and Kostyuk, both of whom also played on Wednesday.
Kostyuk has not enjoyed the most productive start to 2021, but the Ukrainian is yet to celebrate her 19th birthday and has found some form at the WTA Istanbul Cup.
The teenager opened her campaign by accounting for fellow young gun Kamila Rakhimova, a qualifier from Russia, in straight-sets and she backed that up with an excellent 6-3 7-5 upset win over 4th seed Daria Kasatkina.
Konjuh, from Croatia, is on the comeback trail after a succession of injuries, and remains ranked outside the top 200, but she has played some fine tennis this season and looked sharp in beating Sara Errani and Wang Qiang, losing just 12 games in the process.
This looks likely to be a close contest, with Konjuh having more big-match experience and clay-court pedigree despite her lengthy absence from the game.