Ash Barty has become the first woman since Lindsey Davenport in 2001 to win both the singles and doubles titles in Stuttgart.
The World No.1 celebrated her birthday weekend by winning two titles - and a brand new sports car - at the Porsche Tennis Grand Prix after a third consecutive comeback triumph in the singles final against Aryna Sabalenka.
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To complete another landmark week, the 25-year-old then won the doubles title with American partner Jennifer Brady.
Barty had just over an hour's rest before joining forces with her friend, Australia Open finalist Brady, to beat the top-seeded US pairing Bethanie Mattek-Sands and Desirae Krawczyk 6-4 5-7 [10-5].
It made Barty the first reigning World No.1 since Justine Henin in 2007 to win in Stuttgart and the first since Davenport 20 years earlier to win both finals at the same tournament there.
"It's extremely humbling to be even mentioned in the same sentence as both Justine and Lindsay, they're both legends of the game," she said.
After her singles win, Barty was presented with her 68,570 Euros ($A107,074) winner's cheque and a brand new Porsche.
It was another performance full of skill and resilience to dismantle the Belarusian's power game and win 3-6 6-0 6-3 for her third singles title of the year.
For the third day running after come-from-behind wins over Karolina Pliskova and Elina Svitolina, the Queenslander dug deep on the indoor clay after dropping the first set.
Sabalenka, who needed a medical timeout at the end of a second set drubbing, was in tears at one of the changeovers in the deciding final set, struggling not just with a heavily-strapped right thigh but also with Barty's supreme, bamboozling all-court game.
Sabalenka said she had been suffering a lot of pain from an adductor muscle issue that had flared up in the first set.
Tennis world in awe of Ash Barty brilliance
The triumph, Barty's 10th successive over a fellow top-10 player, saw her shoot to the top of the WTA's 'Race to Shenzhen', the order of merit system that identifies the year's top woman player.
It was her first European tournament on clay since triumphing in the 2019 French Open and she looked in the sort of form to regain the trophy that she decided not to defend last year.
"There is a first for everything, isn't there?" laughed Barty after being asked if it was the first time she'd won a bright green Porsche and two titles at the same tournament.
"This week's been phenomenal for me. I've certainly felt like I'm taking my tennis to a kind of a new level in a sense of being able to be calm and play with freedom and play without consequence in a way."
— wta (@WTA) April 25, 2021
Her singles victory had been beautifully constructed after Sabalenka's destructive hitting helped her earn her the one crucial break for 5-3 in the opener but Barty's response was remarkable, as she reeled off nine straight games.
Soaking up the pressure and mixing up her responses with immaculate angles and depth to her shot-making, Barty was at her brilliant best on a lively indoor clay-on-boards surface she'd never experienced before.
And although Sabalenka fought on, Barty, who hammered 26 winners and broke the Belarusian's delivery five times, held off her attempt at one last show of defiance to prevail in one hour 47 minutes.
"She's No.1, she's on top - and she's a great player," was Sabalenka's verdict, one that is being shared throughout the game.
Great title win by Barty in Stuttgart. At home on clay. Still surreal without a crowd. We might be isolated but I wouldn’t trade places.#WTA
— Richard Hinds (@rdhinds) April 25, 2021
2019 French Open champion Ash Barty is champion at her first red clay event since, beating Aryna Sabalenka 3-6, 6-0, 6-3 in the WTA Stuttgart final.
#1 Barty was a surprise champ in Paris last time, but she’s a reasonable choice as favorite for Paris this year.
— Ben Rothenberg (@BenRothenberg) April 25, 2021
As @Daria_gav might suggest, apparently Ashleigh Barty is pretty good from behind, at least this week.
— Anand Datla (@SportaSmile) April 25, 2021
Ash Barty's win in Stuttgart reaffirms her status as World #1. I'm very confused by people questioning her worthiness of the ranking - she's arguably the most well-rounded player on tour. She can excel on any surface, has insane variety, & great fight.
I'm all in! #BartyParty
— james fishon (@jamesfishon) April 25, 2021
I absolutely love barty's game it's so Henin-ish mixed with Clijsters/mauresmo. Taming a beast of a Sabalenka and surviving through close matches. Insane mental prowess and as much I hate to admit she's becoming an all-court player.
— Gauri (@GauriAwasthi5) April 25, 2021
I have so much time for Ash Barty. Awesome sportswoman, incredible competitor, and always comes across as very likeable and down-to-earth too.
— Ellen Marshall (@lenmarsh) April 25, 2021
Watch 'Mind Games', the new series from Yahoo Sport Australia exploring the often brutal mental toil elite athletes go through in pursuit of greatness:
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