In the latest chapter of a rivalry that dates back 13 years, Victoria Azarenka got the better of Petra Kvitova on Sunday night at the BNP Paribas Open in a tight 7-5, 6-4 victory to reach the fourth round.

The two major champions traded breaks three times in the opening set, and Azarenka won the last three games to take it — saving three break points to stave off a first-set tiebreak. The second set proved much the same. Kvitova won four straight games from 3-1 down to take the lead before Azarenka again one a trio of games to seal victory.

In 1 hour and 49 minutes, there was little to separate the two players in the stat line. Azarenka hit 25 winners, and nine aces, to 18 unforced errors, and went 6-for-11 on break points.

Needing treatment on her right thigh in the match, Kvitova struck 29 winners to 26 unforced, but went only 4-for-12 on break points in her last match of the season.

"It was really exhausting year," Kvitova said. "Since COVID started, it's pretty exhausting I think for everybody. My body is just not really handling perfectly. That's why I'm ending right now, to take some extra weeks to recover my body, to heal everything what is there.

"Overall the season, well, I definitely had better seasons than this one. I had a title, which is always the highlight of the season. I played some incredible matches, I would say. I still have the fire inside me, which is very important for me as well, even in this age. I mean, without the fire I think I couldn't play anymore, but it's there so that's nice."

A rivalry renewed: Azarenka and Kvitova were playing for the ninth time overall, but just the third time in the past decade. Azarenka secured her fourth win in their head-to-head matchups, her second on hard courts and first since Toronto in 2015. 

"I think it was a good match," Azarenka said. "It was very close, which I knew it was going to be, going to be kind of hard to catch rhythm. It was a lot of firsts, whoever gets the opportunity to kind of move the ball first, be aggressive. I wasn't expecting too many big rallies. 

"I thought it was good. I'm happy with the way I closed out the both sets. I think those were important moments. I took those opportunities into my own hands.

"It was important to just stay there, really take my opportunities, not to let her. If she gets in the groove in couple points, not to kind of let her extend that streak, if you want to call it that.

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Compatriot clash up next: The two-time major-winner next faces her fellow Belarusian Aliaksandra Sasnovich for a place in the last eight. Despite meeting Aryna Sabalenka four times in the past two years, Azarenka and Sasnovich have never played.

"I think about five years ago, I didn't really have that many players here on tour from my country," Azarenka said. "To see that development of girls and boys ... it's really amazing to see how much tennis is developing from such a small country with not that many resources. I'm really proud of that."

Later, in her post-match press conference, the elder Belarusian expanded on her analysis of her younger compatriot, who'll be bidding for a third straight victory over a Grand Slam champion at this tournament after upsetting Emma Raducanu and Simona Halep.

"First of all, I'm very happy that Sasha has progressed into the fourth round," Azarenka said. "She had a little bit I think less good results lately, so it's an awesome achievement for her.

"It's going to be an interesting match. I think she's playing very freely, nothing to lose. There's always a bit of danger in opponents like that. But I'm honestly looking forward. I know everybody say that they want to focus on themselves, but I am really here to focus on how I can improve my game.

"I think it takes sometimes really time to understand that maybe there are some things that needs to be changed. This is where I am. I want to see how I can implement those changes and work forward."

Fernandez extends Top 20 winning streak with three-set comeback

US Open finalist Leylah Fernandez rallied from a set and a break down to defeat No.9 seed and French Open finalist Anastasia Pavlyuchenkova 5-7, 6-3, 6-4 to advance to the round of 16 in her tournament debut. 

The win extended the Canadian's winning streak against Top 20 opponents to five, including wins over Naomi Osaka, Angelique Kerber, Elina Svitolina, Aryna Sabalenka and now Pavlyuchenkova.

There could only be one winner in the third-round match between two of 2021's major finalists, and Fernandez came from 7-5, 2-0 down to book a meeting with American Shelby Rogers for a place in the quarterfinals.

Ferocious Fernandez comeback upends Pavlyuchenkova in 3 sets: Indian Wells Highlights

Art of the upset: In the aftermath of 7-5, 2-0, Fernandez crucially saved all six break points she faced. The pair traded breaks twice at the end of the first set, with five of the last six games from 3-3 going against serve.

In the second set, the Canadian denied Pavlyuchenkova four opportunities to move ahead 3-2, and she also dug out of 15-40 in the eighth game of the decider to keep the lead. She had previously earned the deciding service break at 2-2. 

Stats of the match: Though both players tallied more unforced errors than winners, it was the Canadian's margin of 24 to 36 that edged the Russian's 32 to 46. In all, the match saw nine breaks of serve between the two, as they combined to create 23 break points. 

Up next: An underdog in each of those five wins against Top 20 foes, Fernandez takes an 0-1 head-to-head record to court against Rogers up next. The pair played last year in Lexington in the round of 16 in a match won by the American, 6-2, 7-5. 

Pegula secures another Round of 16 berth at a WTA 1000 event

Authoring another deep run in a big event, No.19 seed Jessica Pegula eased into the fourth round with a 6-4, 6-1 victory over Italian lucky loser Jasmine Paolini. On court for less than an hour, Pegula wrapped up the 58-minute victory by winning 18 of the final 19 points.

Hitting 16 winners to 16 unforced errors, Pegula went a perfect 5-for-5 on break points. The American boasted a commanding edge in the stat line as Paolini hit just three winners to 23 unforced. 

Fast facts: Pegula has reached the fourth round or better at five WTA 1000 events this year. This also marks her best run in Indian Wells, too, after losing in the first round in her 2012 debut and in the second round in 2019.

Words from the winner: Despite a difference of nearly 40 places places between Pegula and Paolini in the rankings, the American wasn't looking past the Italian who'd beaten No. 14 seed Elise Mertens in the second round and won her first WTA singles title in Portoroz, Slovenia, two weeks ago.

"I knew it was going to be tricky," Pegula said after the match. "I know she was a lucky loser, but she just beat a really good seed, so I knew I couldn't let up. She's really feisty and has a good game, so I just tried to stay aggressive and really focused each point and not get too frustrated, and I think I did a really good job of that.

"I can't believe [this year is] already almost ending. It's gone by really fast, but it's obviously the best year I've had in my career. I've just tried to enjoy every match, still have fun with it, and always keep learning because I think going into next year too, that's what I'm going to have to do, no matter what. I think as long as I'm working on stuff every single day that it makes the process really fun and doesn't put too much pressure on me."

Back to the beginning: For a spot in the quarterfinals, Pegula will face Elina Svitolina for the third time this year. To begin her breakthrough season, she defeated Svitolina in the fourth round of the Australian Open in February for her first Top 10 victory. She has since scored five more.

Read more: Sasnovich shocks Halep to extend Indian Wells upset run; Svitolina outlasts Cirstea

"It's a huge opportunity," Pegula said. "I obviously know it's going to be a tough match. I think once you're deeper in the tournament, every match gets harder and harder. I know that I've beaten her before but now she's watched me play all year, and I'm sure she has a different game plan or she's going to do something different.

"I actually really admire how she competes. I think she's probably one of the best competitors, if not the best, out there, so no matter what, I'm going to have to go out there and compete hard, and hopefully, it'll be a good match."