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Upset artist Kaia Kanepi strikes again.

The 35-year-old Estonian veteran powered past defending champion and No.4 Sofia Kenin of the United States, 6-3, 6-2, eliminating the highest-seeded player from the tournament thus far as she moves into the Australian Open third round for the third time.

Despite the disparity in their rankings -- Kanepi is currently World No.65 to Kenin’s No.4 -- Kanepi has executed a litany of upsets throughout her career. This is her 13th victory over a current Top 10 player, eight of which have come at Grand Slam tournaments.

"I'll take one match at a time and one tournament at a time and it all depends how I feel and how the opponent plays and so on," Kanepi said, in her post-match press conference. "But I played good today, I served really good and I think it was a good win."

Former World No.15 Kanepi has also won six of her seven matches this season, having reached her first WTA singles final since 2013 just last week at the Gippsland Trophy in Melbourne Park. Kanepi collected one of her patented stunners during last week’s run, spectacularly ending the 15-match winning streak of World No.7 Aryna Sabalenka in the second round.

"This year I think it helped that I got many matches in the previous week to get used to the conditions," said Kanepi. "I also played many matches on Margaret Court and I also played there today, so I think that also helped to feel better."

Kanepi needed just 64 minutes to take out Kenin on Thursday, ending the reigning champion's eight-match winning streak at the Australian Open. The power game of Kanepi was particularly consistent today as it has been for much of the Aussie swing: the Estonian slammed 22 winners (including 10 aces) to just 17 unforced errors on the day.

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The match was typified by the final game, where a 15-30 deficit was erased by Kanepi with three straight aces to claim the win and stun last year's titlist.

"I obviously felt like I couldn't find my rhythm," Kenin told the media, after falling to 0-2 against Kanepi. "I was obviously way too nervous."

"I mean, she played really well," Kenin continued. "She came up with some good shots. She obviously had a good plan against me. I just couldn't execute my shots."

Kanepi has reached six Grand Slam quarterfinals in her career, but the Australian Open is the only one of the four majors where she has yet to make the elite eight.

However, Kanepi says that statistic is something that isn't in her mind. "I don't think about that any more," Kanepi said. "I just think that I enjoy what I do and I feel good, and that's it."

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In order to keep her current run going, Kanepi will next have to face down No.28 seed Donna Vekic of Croatia.

Vekic booked her spot in the third round with a swift win of her own, dispatching 2020 Roland Garros semifinalist Nadia Podoroska, 6-2, 6-2, in an hour on the dot.

Bencic, Mertens set up third-round tussle

A battle between Top 20 players will take place in the third round of the Australian Open, as No.11 seed Belinda Bencic and No.18 seed Elise Mertens will square off on Saturday.

Switzerland's Bencic survived a barnburner against two-time Grand Slam champion Svetlana Kuznetsova of Russia, prevailing 7-5, 2-6, 6-4 in two hours and 39 minutes.

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Svetlana Kuznetsova (L) and Belinda Bencic shake hands after their second-round match at the 2021 Australian Open, which Bencic won in three sets.

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"It was a tough match, as I expected against Kuznetsova," Bencic said in her post-match press conference, after extending her head-to-head lead over the Russian to 4-2. "I was happy with the way I fought, super happy about the win of course. But, yeah, it was not easy out there. I just tried to tough it out."

In a deciding set where the returner held the edge more often than not, Bencic broke Kuznetsova four times, including in the last game, to eke out the hard-fought victory and set up her clash with Mertens.

"I definitely think she's a very consistent and solid player," said Bencic, looking forward to her Mertens meeting. "I played her in juniors, but not in WTA yet. I'm looking forward to the match. I will definitely relax my mind today and tomorrow and just get back focusing tomorrow evening and try to find a tactic against her and a game plan."

Mertens, meanwhile, continued her run of good form with a challenging win of her own, defeating Zhu Lin of China, 7-6(8), 6-1.

Belgium's Mertens, coming off her sixth career WTA singles title at the Gippsland Trophy last weekend (where she defeated Kaia Kanepi in the final), fended off two set points in the first-set tiebreak against World No.94 Zhu.

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Elise Mertens during her second-round match at the 2021 Australian Open.

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After claiming that set in a grueling 67 minutes, Mertens eased through the second set to make it into the Australian Open third round for the fourth time in her four main-draw showings.

"I think the first set was really tight, how she got to the ball," Mertens said in her post-match press conference. "I was really happy just to get it done in two sets and especially win the first one.

"I think I played a bit more aggressive in the second set, a bit better, first serve was coming in more, so that definitely made a difference."

Mertens's best result at the year's first major came in her initial appearance in the main draw, where she made it all the way to the 2018 semifinals.

Unbreakable Brady blasts into round 3

No.22 seed Jennifer Brady came out the victor in an all-American second-round clash, as she swept past Madison Brengle, 6-1, 6-2, in just 52 minutes.

"I’m really happy with the way I was able to serve today, just play aggressive tennis and come out with a win," Brady said, after her triumph.

The 2020 US Open semifinalist has only dropped seven games in her first two matches, as she awaits the winner of an all-qualifier battle between Mayar Sherif and Kaja Juvan.

Brady was blistering on serve against Brengle, firing five aces and never facing a break point (she also faced no break points in her first-round victory). Brady had 29 winners on the day, to 85th-ranked Brengle's six.

Brady is now just a win away from matching her fourth-round run in her debut main-draw appearance at the Australian Open, which came in 2017.

"I have a lot more confidence in myself and my game," said Brady. "I don’t really stress as much, I would say. During matches, I think I’m feeling confident hitting my shots and going for my shots, trusting in my game and myself regardless of what the score is, and knowing that if I’m serving well and looking for my forehand, then I have a pretty good chance of winning the match."