Billionaire daughter's classy act after never-before-seen feat

Jessica Pegula may be the daughter of American billionaires, but the tennis star has demonstrated a superb sense of grounding with a wonderful gesture for a rival player on Monday.

The giant-killing American continued her extraordinary Australian Open charge with an upset win over fifth seed Elina Svitolina in the fourth round.

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The unseeded 26-year-old has been in scintillating form at Melbourne Park and overwhelmed the Ukrainian 6-4, 3-6, 6-3 to book her spot in the quarter-finals.

Pegula's parents Terry and Kim Pegula own the Buffalo Bills and Buffalo Sabres sport franchises, and have a net worth of more than $5 billion, according to Forbes.

They were both on the American's mind after her stunning fourth round victory against Svitolina, which marked the first time Pegula has beaten a top-10 player in her professional career.

In a moment of class after the momentous victory, Pegula left a message to her parents on the courtside camera, as well as one for compatriot Jennifer Brady, who was playing Croatia's Donna Vekic straight afterwards.

"See you in next round, Jen B," she wrote on the camera alongside a shout-out to her famous folks.

Pegula's touching prediction for her compatriot came true as Brady dispatched Vekic 6-1 7-5 to set up an all-American quarter-final showdown.

Ranked just 61 and playing only her second Australian Open, Pegula took out former world number one and 12th seed Victoria Azarenka in the opening round then dropped just four games in her next two matches.

American rivals square off for place in last four

Svitolina had won in straight-sets when the pair met at Abu Dhabi last month but it was Pegula who took the initiative Monday, creating three break points that were saved before a double fault on the fourth handed her a 4-3 lead.

She held serve to consolidate her advantage and take the set after some punishing baselines battles.

They traded breaks early in the second set before Svitolina held then broke again for 3-1 as Pegula temporarily lost focus.

But Pegula, who missed most of 2017 with a hip injury that forced her to consider retirement, bounced back in the decider and secured a crucial break in the fourth game with a backhand volley winner.

A double fault allowed Svitolina back, but Pegula broke again for 5-3 and served out for her biggest win.

"I really admire how she is on the court, she just puts her head down and goes about her business and really always fights, so that's definitely something I tried to do today," Pegula said of Svitolina.

"I think with the nerves and the end of the first set being tough I got a little tired. But I feel good now."

Brady - who made a breakthrough run to the semi-finals at last year's US Open - had a more straightforward progression to the last eight in her win against Vekic.

Croatia's No.28 seed had been beaten in the opening round at her previous five tournaments.

She took a medical time-out after winning the opening game of the second set to have treatment on her heavily-strapped right knee before deciding to continue.

Vekic showed plenty of fight to make things tough for the American in the second set but the big-serving Brady has now won all four of her matches at Melbourne Park in straight sets.

"I'm super excited to be in the quarter-finals," said the No.22 seed.

"It was a really tough match."

with agencies

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