No.8 seed Elise Mertens delivered a battling performance to quell Alizé Cornet 3-6, 6-2, 6-4 in the first round of the St. Petersburg Ladies Trophy, coming from a break down in the third set to do so.

Mertens had not beaten Cornet since 2018, having lost to the Frenchwoman in straight sets in both the 2019 Billie Jean King Cup and Charleston last year. Cornet, who reached her first Grand Slam quarterfinal in her 63rd attempt last month at the Australian Open, began confidently again but was gradually reeled in over 2 hours and 8 minutes.

Mertens will next bid to reach her first quarterfinal of 2022 against either Petra Martic or wildcard Kamilla Rakhimova.

Match management: Both players fired 13 winners in the first set, but No.37-ranked Cornet kept a tighter ship with 14 unforced errors to Mertens' 24. One of the latter, a wayward dropshot attempt into the middle of the net, handed Cornet the crucial break of the set for 4-2.

But a rejuvenated Mertens raised her level significantly in the second and third sets, finding 31 winners to 32 unforced errors. Striking her forehand with greater accuracy and aggression, the Belgian brought up her first break points of the match in the second game. Though Cornet staved off that danger and found several touches of magic on the dropshot, Mertens' form was irresistible. The World No.26 came out on top of three consecutive deuce tussles from 3-2 to break Cornet twice and level the match.

As the pair engaged in all-court exchanges with increasing frequency, the contest built to a gripping climax. Mertens twice went down a break, and trailed 3-2 after committing her fifth double fault. But she levelled at 3-3 after Cornet found the net with a backhand, and put away a athletic drive volley to bring up a match point opportunity at 5-4 - sealed as Cornet sent a backhand wide.

In Mertens' words: "It was a very tight match," she said aftewards. "It could go either way, it was a battle - it's always difficult against her but I just kept fighting. I think I raised my level a little bit in the second and third sets. I stepped more into the court, the service was a bit better and I ran better."

Kontaveit, Bencic, Alexandrova advance in deciding sets

Third sets were on trend on Day 1 of the tournament, with all four scheduled main-draw matches going to a decider. In addition to Mertens' win, No.2 seed Anett Kontaveit survived 6-3, 1-6, 6-3 against Jil Teichmann; No.5 seed Belinda Bencic came from a break down in the third set to squeeze past Veronika Kudermetova 6-2, 4-6, 7-6(5); and Ekaterina Alexandrova scored a 6-2, 1-6, 6-2 win over Camila Giorgi on home soil.

Bencic, the 2016 runner-up, has been squaring off against fellow 1997-born Kudermetova since their teenage days. The Swiss dominated their nascent rivalry, winning all three of their junior encounters, but Kudermetova turned it around at pro level to triumph in three out of four matches between 2018-19 - including a 6-4, 6-3 victory in St. Petersburg qualifying in 2019.

The pendulum has swung again in the past three years as Bencic has now taken three consecutive tight three-setters over Kudermetova. This result was remarkably similar to her 6-4, 4-6, 7-6(4) win at Doha 2020 and her 6-4, 5-7, 6-4 win at Dubai 2021, with both players reliant on the quality of their serves and looking to end points as quickly as possible.

Highlights: Alexandrova d. Giorgi | Kontaveit d. Teichmann | Bencic d. Kudermetova

This resulted in a high unforced error tally for both - Kudermetova committed 84 to Bencic's 67 - but plenty of unreturnable serves and one-two punches to balance those. Ultimately, Bencic tallied one more winner, 52 to Kudermetova's 51.

Bencic's first serve was the crucial weapon: she dropped just 12 points on it across the whole match, and only one in a dominant first set. Her first-serve percentage dipped in the second set, allowing Kudermetova a foothold in the match, and a trio of double faults at the start of the decider dug an even deeper hole for Bencic.

However, Kudermetova's own serve was more attackable for Bencic, and the Russian did not deliver the rally tolerance needed to out-manoeuvre the former World No.4 in rallies. Nonetheless, Kudermetova did come up with the shot of the match - a perfectly placed backhand winner off a putative drive volley putaway from Bencic.

Juvan, Niemeier, Peterson, Gracheva qualify

The final round of qualifying saw Kaja Juvan edge out Caty McNally 6-4, 3-6, 6-3, while Jule Niemeier halted the run of 17-year-old wildcard Erika Andreeva 4-6, 6-1, 6-1. No.304-ranked Andreeva, the 2020 Roland Garros girls' runner-up, had posted the first Top 100 win of her career over Kristina Mladenovic 6-3, 6-7(8), 7-5 in the first round of qualifying, and backed that up with another quality victory over Viktoria Kuzmova 7-5, 4-6, 6-1 in the second.

The last two qualifiers were No.1 seed Rebecca Peterson, who turned her match against Bernarda Pera around emphatically to win 5-7, 6-0, 6-1, and No.3 seed Varvara Gracheva, who ended Ana Bogdan's seven-match winning streak 6-4, 6-4.