'Not giving up': Ash Barty comeback stuns former World No.1

Ash Barty has produced another brilliant comeback to advance to the Miami Open quarter-finals, beating Victoria Azarenka in three sets.

After dropping the first set against Barty 6-1 on Monday, Azarenka threatened to produce a massive boilover when she claimed the second with a 6-1 win of her own.

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However the Aussie star produced a brilliant fightback to claim the deciding set 6-2.

Barty's first serve was strong as she controlled the first set against the former World No.1, delivering six aces.

But Azaranka, a three-time Miami Open winner, hit back with five straight games to take the second.

Barty, the reigning Miami Open champion, then settled in the third to advance to the last 16 of the WTA 1000 event.

It was Barty's 17th win in her last 20 three-set matches, proving how tough she is to beat when she's on the ropes.

"It's just about staying in the fight," Barty said.

"It's about not relenting, not giving up regardless of whether you lose a set or you get a break, whatever it might be.

"I've worked my backside off off the court to make sure that I feel like I'm good physical condition to play tennis."

Barty will next face Aryna Sabalenka, who beat Marketa Vondrousova 6-1 6-2.

Barty and Naomi Osaka on collision course

Reigning US and Australian Open champion Naomi Osaka also advanced to the quarter-finals on Monday, stretching her win streak to 23 matches by defeating Belgian 16th seed Elise Mertens 6-3, 6-3.

"I started off really well and then for some reason I became a little sluggish. My speed didn't really feel the same," Osaka said after the match.

"I thought it was really mental from then on. In the end, it was who fought the hardest."

The four-time grand slam champion broke at love for a 2-0 lead and broke again for a 5-1 edge.

However Mertens broke Osaka at love in the seventh game and denied four set points for Osaka to hold in an eighth game that lasted almost 10 minutes.

Osaka, seeking her first Miami crown, saved a break point with her third ace and finally finished off the first set on her seventh chance with a service winner.

In the second set, Osaka needed her fifth chance of the third game to break Mertens, only for the Belgian to quickly break back to 2-2 and hold to 3-2 before requiring treatment for a right shoulder injury.

Osaka won the last four games after that, breaking at love in the seventh game, holding at love in the eighth and breaking again to end matters after 88 minutes when Mertens netted a forehand.

The World No.2 is looking to make up ground on Barty in the world rankings, with the World No.1 needing to defend her title to avoid losing points.

Ukraine's fifth-seeded Elina Svitolina rallied to defeat Czech ninth seed Petra Kvitova 2-6, 7-5, 7-5.

"I'm really happy with how I bounced back from being a set down," Svitolina said.

"I'm happy with how I'm playing and handling the pressure. I had to bring my best game to win."

with agencies

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