MELBOURNE, Australia -- Elise Mertens of Belgium finds herself on a seven-match winning streak, as she ousted France's Alizé Cornet, 7-5, 6-4, at the Australian Open on Friday, and reaches the first fourth-round appearance at a Grand Slam in her career.

"It was a very hot day," Mertens told the press, after her late doubles match. "I think everybody’s struggling a little bit -- my opponent too, in the second set. But I was also struggling today...This time, it’s difficult to not show it, but I tried to cover it a little bit."

Mertens, who defended her Hobart International title last week, and had a stunning late-night win in Melbourne two days ago, is making her first ever appearance in the main draw of the year's first major, and indeed was forced to miss the qualifying event in 2017, as she was busy claiming the first WTA title of her career in Hobart.

The World No.37 was more effective on serve than Cornet, winning 76 percent of her first service points, and 60 percent of her second service points (compared to 54 percent and 51 percent respectively for Cornet). This became the crucial difference in a match which featured an astounding 12 breaks of service over just two sets.

Mertens took a commanding lead in the first set, racing to a 4-1 advantage before Cornet got her feet under her. Cornet then took Mertens’ next two service games, to tie the set at 4-4, as both players engaged in spirited rallies in temperatures of over 100 degrees.

But Mertens would prevail in the opener. Serving at 5-5, Cornet hit a double fault and two unforced errors to give Mertens triple break point, and the Belgian broke for a 6-5 lead on her second opportunity. Mertens refused to let another lead slip away in the set, and a strong serve which Cornet returned into the net gave the 22-year-old a one-set advantage.

As the second set got underway, Cornet was struggling with the heat far more than Mertens was. The players exchanged breaks in the first two games of the set, but Mertens reclaimed a one-break lead in the dramatic next game, when Cornet double faulted to bring up break point, then voluntarily laid down on the court, overcome by the heat.

Cornet did rise of her own volition to finish the game, but meekly netted a forehand, and immediately received a medical time out. After the break, Mertens held easily, and then broke Cornet again, at love. Up a set and 4-1 with a struggling opponent, it seemed that Mertens would finally obtain her Grand Slam breakthrough.

But Cornet, currently ranked five spots behind Mertens at No.42, would not give up, and the combatants entered into an array of breaks, where both players were being aggressive on return, and double faulting too much on their own serves. By 5-3, seven of the eight games in the set had gone against serve.

Cornet, playing much more freely at this point, easily held for 5-4 with a stunning down-the-line winner, and with Mertens’ serve shaky, the Frenchwoman seemed confident despite her physical woes. 

And, indeed, the 5-4 game was a marathon, with Cornet saving three match points and Mertens saving two break points before Cornet hit a backhand into the net on the Belgian’s fourth match point. Mertens jumped for joy and hugged her worthy competitor at the net, and will look forward to her first fourth-round match at a Grand Slam, where she will face Petra Martic of Croatia.

"I hope to do more, to do well, and we’ll see where it ends," said Mertens. "I’m not going to say ‘Ooh, I’m really happy to be in the fourth round!’ I am, but still, at this stage, I’ll try to keep myself motivated. There’s still energy left, and I feel like I can do more."

Suárez Navarro subdues Kanepi: Former World No.6 Carla Suárez Navarro of Spain came back from a one-set deficit against powerful Estonian Kaia Kanepi, edging the six-time major quarterfinalist, 3-6, 6-1, 6-3, in one hour and 43 minutes.

"It was tough today, I was one set down, and she played really fast, really good in the first set," Suárez Navarro told WTA Insider after the match. "For me, it’s not easy, it’s difficult."

The Spaniard used her variety of shot and superb defense to eventually quell the thunderous shots coming off of the Estonian's racket, thereby denying Kanepi a fourth-round spot at the one major where she is yet to reach that point.

Suárez Navarro thus advances to a fourth-round encounter against either reigning French Open champion and No.7 seed Jelena Ostapenko of Latvia or 32nd seed Anett Kontaveit, Kanepi's compatriot.

"I’m really happy, because I feel that I need it [the fourth-round result]," Suárez Navarro continued. "I was practicing really good in the off-season, and the results that I had in Sydney and Brisbane, I didn’t like them. But I feel like I’m playing good, I have the level and I can be there, and I want more."

Kanepi had 32 winners to Suárez Navarro's 18, but Suárez Navarro was overall more effective on serve, winning 64 percent of her first service points.

It did not initially appear that the match would go Suárez Navarro's way, as the brutal groundstrokes from Kanepi were easily finding their spots. Incredible forehands from the Estonian were cleaning the lines en route to a 5-1 lead, and although Suárez Navarro dragged the set to 5-3, Kanepi held to love with some exceptional serving to clinch the first set.

But the guile of Suárez Navarro came through with flying colors in the second set, and Kanepi started to misfire, especially, at the end of the set, off of her backhand side. Kanepi only had three winners in the set -- Suárez Navarro had four -- and it was a breeze for the Spanish player to level the match.

Suárez Navarro kept her solid game rolling in the decider. She broke Kanepi in the first game of the set with a lovely backhand volley winner, and clubbed another winner with her aesthetically pleasing one-handed backhand to break for a 4-1 lead. Suárez Navarro was also tactically sound at this point, picking on the Estonian's backhand, which had not recovered as of yet.

Kanepi, however, caught fire at the end of the set, diminishing her unforced errors and finding holes in the Suárez Navarro serve. Yet Kanepi was struggling to close out her own service, and the final four games of the match were breaks of service.

Thus, the early lead obtained by Suárez Navarro proved crucial, and Kanepi double faulted at 5-3 30-30 to give Suárez Navarro a match point. On the next point, a mistimed overhead by Suárez Navarro took an askew bounce, and Kanepi, unable to get into proper position, hit an error to end the match and send a euphoric Spaniard into the second week of the Australian Open for the third time, after quarterfinal appearances in 2009 and 2016.

Rybarikova rebounds: No.19 seed Magdalena Rybarikova of Slovakia won a tumultuous encounter against Ukrainian Kateryna Bondarenko, coming back from three set points down in the opening frame before prevailing in three sets, 7-5, 3-6, 6-1.

The unseeded Ukrainian, currently ranked 94th in the world but a former Top 30 player, had 29 winners in the match, as opposed to 23 from the Slovak. But Rybarikova, a semifinalist at Wimbledon last year, had nine aces and was 4-for-4 on break point opportunities.

Bondarenko served for the first set at 5-3, and zoomed to a 40-0 lead in that game, giving her three set points. But nerves took over and unforced errors crept into her game, and suddenly all of the set points had vanished. Rybarikova reached break point, and Bondarenko promptly double faulted, putting the set back on serve.

Rybarikova took the momentum and ran with it, easily holding for 5-5 before breaking Bondarenko again for a 6-5 lead. The Slovak had to save a break point when serving for the set, but after clawing back to deuce, two good serves were unsuccessfully returned by Bondarenko, completing the first-set comeback.

"[Bondarenko] was playing very well, and I was not playing that well, and I could not find the rhythm," Rybarikova told the press afterwards. "I was fighting with the heat a little bit, and with the wind, and I didn’t feel that great in the beginning...I was happy and lucky to get the first set."

Despite the opening-set collapse, Bondarenko started the second set strongly as well. She broke Rybarikova for 2-0, and then held to take a 3-0 lead. After this game, Rybarikova took an off-court medical time-out, and appeared to be struggling with her movement in the heat.

Bondarenko once again took a 5-3 lead in the second set, and this time, the Ukrainian served through any anxiety, leveling the match at one set apiece and seemingly taking command of the match.

"In the second set, again, she was playing very well, very aggressive," Rybarikova continued. "I was again struggling in the shadows, and I was complaining and was not really good. I didn’t feel great, I have to say, in the second set."

In the deciding set, Rybarikova shifted the momentum again, and utilized her wily skills to dismantle Bondarenko down the stretch. Rybarikova broke to lead 2-0 after Bondarenko double faulted down break point, and then held at love to race to 3-0.

An additional break for 5-1 -- again via a Bondarenko double fault -- made the stern task of serving out a match that much simpler, and a crafty slice backhand from the Slovak forced an error from Bondarenko to close out the match in two hours and four minutes.

"Third set, I was like a totally different person," Rybarikova told the press. "I was playing really well, I went for it, I was aggressive. The shadows went away, so I was liking that, and I really felt great, and the heat wasn’t that bad."

"So, for me, the [first] two sets were so-so, but the third set was very good."