No.1 seed Ashleigh Barty and No.7 seed Aryna Sabalenka each fended off match points Thursday before outlasting their opponents in the second round of the Miami Open.

World No.1 Barty overcame qualifier Kristina Kucova 6-3, 4-6, 7-5 in two-and-a-half hours. Barty was forced to save one match point while down 3-5 in the third set, in the midst of reeling off the final five games of the clash.

"Never give up, never ever give up," Barty said in her on-court post-match interview. "You’re always in there with a chance."

Sabalenka, meanwhile, saved two match points in the decisive final-set tiebreak before quashing qualifier Tsvetana Pironkova 0-6, 3-6, 7-6(9), also in two-and-a-half hours.

Barty, who returns as defending champion having triumphed at the most recent edition in 2019, was playing her first match outside of Australia in over a year. Barty hit 15 aces, tying her career-high for aces in a match (she also hit 15 aces in the 2019 Miami final).

The World No.1, who is 25-1 in matches where she hits 10 or more aces, also finished with no double faults. This is only the ninth time since 2008 where a player has hit 15 or more aces with zero double faults.

Barty's first set was relatively straightforward as she used her excellent volleying to charge back from an early break down and grab the one-set lead. Barty had 11 winners to Kucova's two in the opening frame.

However, Kucova made her mark in the second set after dropping serve in the first game. The qualifier struck back right away to get level, then held on through 5-4 to push the top seed. With Barty serving at 30-0 in that game, Kucova reeled off three straight points to suddenly reach set point, and after a Barty forehand flew long, the qualifier had tied up the match at one set apiece.

Playing for the first time against a reigning World No.1, Kucova continued to hold the momentum as the decider kicked off. Kucova used her backhand to force an error from Barty as she edged ahead by a break at 3-1. Kucova extended her lead even further as she zipped to match point while serving at 5-3.

But Barty swatted that match point away with a forehand return winner, and she earned the service break as she clawed her way back into the match. Aggressive play at the net gave Barty another break for 6-5, and though she fell behind 0-40 while serving for the match, two aces and a volley winner powered her back to deuce, and she held on from there for victory.

"Today was really hard work, and I enjoyed every single minute of it," Barty said on court. "There’s nothing like coming through a test like that, and now I get another opportunity in a couple days time to play another tough match, and test myself again."

How Barty saved MP and avoided an early exit in Miami

For Sabalenka, her first meeting with Pironkova proved to be topsy-turvy, but the World No.8 at last came back from a set and a break down to deny Pironkova her first Top 10 win since 2016 Roland Garros.

Sabalenka said on-court: "Since a young age, my parents keep telling me, ‘It doesn’t matter what goes on in the court, you just have to fight, and if you will fight, you will get the wins.’"

Pironkova sailed through the first set with ease and earned the early break in the second set to lead 3-1, but Sabalenka finally earned break points in the opening stages of that set, eventually pulling back level for 3-3. Spurred on by that, Sabalenka blasted through the final five games of the set to tie up the match.

Pironkova took another early lead in the decider after Sabalenka double faulted to drop serve at love for 3-1, but Sabalenka methodically pulled her way back into the set, and deployed a devilish dropshot winner to get back on serve at 5-4.

The pair advanced to the tiebreak, where Sabalenka used typically aggressive play to ease from 0-2 down to 6-4 and double match point. Deep hitting by Pironkova allowed her to save both at the duo changed ends at 6-6, and it was then Pironkova's chance to hold two match points.

But sturdy down-the-line hitting by Sabalenka pulled her through those challenges, and she grabbed another two match points. Sabalenka finally closed out the match with an overhead winner.

More Grand Slam champions joined 2019 Roland Garros champion Barty in the third round. Barty's successor in Paris, reigning Roland Garros champion Iga Swiatek, claimed a 6-4, 6-2 win over Barbora Krejcikova.

Powerful service returns by Swiatek propelled her to a 5-1 lead, but Krejcikova tightened up her game, at one juncture notching ten points in a row as she pulled back on serve at 5-4 while Swiatek faltered in the breezy conditions. Swiatek, though, rebounded to break for the one-set advantage after Krejcikova misfired on an overhead on break point.

An initially competitive second set started to slide Swiatek's way as she won her third game in a row to ease ahead by a break at 4-2. Swiatek began to ride the wave of momentum, easily holding for 5-2 with a thundering forehand winner, and the No.15 seed took her place in the third round after a Krejcikova double fault on match point.

Later on Thursday, No.24 seed Angelique Kerber's 6-0, 6-0 victory over qualifier Renata Zarazua was the German's first double-bagel victory since she beat her compatriot Carina Witthoeft by that score in the first round of 2015 Wimbledon.

"The score, it's a little bit different than the match was, because [a] few games were like really close and tough," Kerber said, in her post-match press conference.

Former World No.1 Kerber needed just a smidge over an hour to bound into the third round and set up an enticing meeting with another former World No.1, Victoria Azarenka. No.14 seed Azarenka advanced to the third round without hitting a ball after Laura Siegemund was forced to withdraw from their clash due to a right knee injury.

Kerber said she had a "lot of matches against Vika in the past, so I know it's another hard battle against her. But this is why I'm here, to try to play good matches against the best players."

angelique kerber
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9.1% Win 1
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90.9% Win 10
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Kerber had to fend off three break points in the opening game of the encounter, but after escaping that danger, the three-time Grand Slam champion had no trouble finding vintage crosscourt winners to sweep through the opener. Kerber fired ten winners to just four unforced errors in the first set.

The second set was also controlled by Kerber, as she erased two break points at 2-0 en route to saving all five break points she faced on the day. Zarazua, playing in her first WTA 1000 Mandatory event, can look fondly on her opening-round win over Nao Hibino, but she could not upend the sterling play of Kerber, and slammed a double fault to wrap up the affair.

2017 Roland Garros champion Jelena Ostapenko also claimed a victory on Thursday, as she overcame lucky loser Kirsten Flipkens, 6-2, 5-7, 6-3.

Ostapenko converted six of her eight break points against Flipkens, and will now face No.1 Barty in the round of 32 on Saturday.