'What an escape': Tennis world erupts over Ash Barty miracle

Ash Barty has pulled off an extraordinary comeback to advance at the Miami Open, storming back from 2-5 in the third set to win.

Playing in her first overseas tournament since 2019, Australia's World No.1 appeared destined for another shock first-up loss on Thursday.

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Unseeded Slovakian player Kristína Kucova took a 5-2 lead in the deciding set and had a match point to seal it in the next game.

However Barty managed to reel off the next five games in succession to win 6-3, 4-6, 7-5.

Barty fell behind 0-40 while serving in the final game, but rallied once again against World No.149 Kucova.

The Aussie closed out the victory with a service winner, and then tapped her temple with her index finger, as if in tribute to the way she kept her composure in the crunch.

Playing away from Australia for the first time since the COVID-19 pandemic began, Barty won despite an unreliable forehand, whacking 40 unforced errors on that side.

Barty is the defending champion in Miami after winning the title in 2019.

The 2020 edition of the Miami Open was cancelled due to the COVID-19 pandemic.

The Aussie star needs to defend the title or risk losing ground in the rankings to World No.2 Naomi Osaka.

Tennis fans and commentators were left stunned by her remarkable comeback on Thursday.

Kokkinakis and Thompson also advance

Earlier, Thanasi Kokkinakis took another positive step in his comeback from years of injuries by winning his first match in an ATP 1000 tournament for three years.

Adelaide's big-serving Kokkinakis overpowered Japanese teenager Shintaro Mochizuki 6-3 6-3 to move into the second round of the tournament - which holds happy memories for him as the scene of his best-ever win over Roger Federer in 2018.

Kokkinakis's fellow Australian Jordan Thompson also enjoyed a successful day, moving into the second round with a victory over Argentine Federico Delbonis 7-6 (8-6) 6-4.

Qualifier Kokkinakis, who's set to improve substantially on his current world ranking of No. 243, downed the Wimbledon junior champion in 84 minutes to set up a second-round clash against Hungarian No. 29 seed Marton Fucsovics.

After his qualifying wins, it was another impressive step forward for the 24-year-old, who returned to the ATP Tour last month in Melbourne before pushing eventual semi-finalist Stefanos Tsitsipas to five sets at the Australian Open.

"I haven't played in so long, so any match is a good chance to get out there for me to show and prove that I belong to get my ranking back and rebuild some confidence," Kokkinakis said after making the main draw.

His only real concern came in his opening service game when he had to fight back from 0-40 down to hold but the 17-year-old Mochizuki gifted a double fault to allow the Australian to take a 3-1 lead.

Both struggled to hold serve in the second set but the Japanese was broken four times to two as Kokkinakis wrapped up his win in 84 minutes.

"It was amazing to be there," said the beaten teen. "I was confident about the match, but he kept hitting big and he was a lot better than me."

World No.60 Thompson booked his first-ever meeting with Canada's former Wimbledon finalist Milos Raonic after prevailing in a tough battle with Delbonis, who's ranked 20 places below him.

The Sydneysider had to save a set point in the tiebreak of the opening stanza but took control with a break midway through the second set to win a contest lasting nearly two and a quarter hours.

with AAP

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