No.8 seed Ons Jabeur of Tunisia overcame a stern test in her opening-round match at the Dubai Duty Free Tennis Championships, staving off former World No.2 Vera Zvonareva 6-2, 2-6, 7-5.

10th-ranked Jabeur needed just over two hours to defeat Russia's Zvonareva, currently ranked No.103. After losing her first meeting with Zvonareva at the 2015 Australian Open, Jabeur has now won the last two.

More from Dubai: Ruse scores first Top 10 win over Badosa

In her first match since retiring in the Sydney quarterfinals due to a back injury, Jabeur converted five of her 11 break points to book a second-round meeting with World No.14 Jessica Pegula of the United States.

Jabeur eased through the first set before Zvonareva, a Wimbledon and US Open runner-up in 2010, surged back in the second set. The Russian leapt to a quick 4-0 lead and stayed ahead from there to level the affair.

A tense third set saw Zvonareva come back from a break down as she tied up the decider at 3-3. Powerful forehands gave Zvonareva a hold for 5-4, but Jabeur held her nerve and serve to reach 5-5 and extend the clash.

Double faults plagued Zvonareva in the next game as she dropped serve, but she garnered three break points in the following game when Jabeur served for the match. Exquisite placement by Jabeur helped her see off those chances, and the Tunisian closed out the win at last with an unreturned serve.

Kudermetova topples former finalist Azarenka

Another Russian, Veronika Kudermetova, picked up a first-round win, beating former World No.1 Victoria Azarenka 6-3, 6-4 in an hour and a half.

World No.31 Kudermetova never dropped serve and only faced one break point all day against two-time Australian Open champion Azarenka, currently ranked 17th.

Dubai 2022: Draws, prize money and everything you need to know

Azarenka has had success at Dubai before, reaching the final back in 2010, but she was quickly down in the score against Kudermetova, who earned the first break of the day at 3-1 in the opening set and never looked back.

Veronika Kudermetova in action during her first-round win.

Jimmie48/WTA

Kudermetova was mostly untroubled on serve and took charge in the second set as well with a break for 4-3 following a long forehand by Azarenka.

At 5-3, Azarenka saved a match point on her serve to push the encounter one game further, but a missed return on Kudermetova's third match point gave the Russian the victory shortly thereafter.

Collins retires from opener

No.9 seed Danielle Collins of the United States retired from her first-round match against 38th-ranked Marketa Vondrousova of the Czech Republic due to dizziness, 2-6, 3-0, ret.

World No.11 Collins, who reached her first Grand Slam final last month at the Australian Open, took the first set handily but struggled as the second set began.

Read more: Despite falling short in Australia, Collins focused on what's next in her journey

After last year's Olympic silver medalist Vondrousova leapt to a double-break lead in the second set, Collins took a medical time-out, after which the ailing American stopped the match.

2019 Roland Garros runner-up Vondrousova, who qualified for the main draw this week, will face another qualifier, Varvara Gracheva of Russia, in the second round. Gracheva defeated Australian lucky loser Ajla Tomljanovic 6-1, 7-5.