No.1 seed Ashleigh Barty underlined her dominance of the Tour with a 6-1, 3-6, 6-3 defeat of No.9 seed Petra Kvitova in one hour and 48 minutes to reach her first Mutua Madrid Open semifinal.

There, she will face a rematch against the only player to have beaten her since February - wildcard Paula Badosa, who became the first Spanish woman to reach the last four in Madrid with a 6-4, 7-5 upset of No.8 seed Belinda Bencic.

Barty's reign is borne out in the numbers. The Australian has extended her winning streaks on red clay to 15, and against Top 20 opponents to 10. Her season record is 24-3, and she has won five of her past six meetings with Kvitova to tie their overall head-to-head at 5-5. Moreover, Barty has also now won 11 of the 12 three-setters she has played in 2021.

"It's just always staying in the fight," said Barty about her record in deciding sets. "Always staying in the hunt and never letting it slide away. That certainly doesn't guarantee results, doesn't guarantee success. It guarantees you give yourself the best chance to do what you do and to figure it out and to find your way.

"I think it's important not to panic, but everyone emotionally has different ways that they play on the court. I have always been quite calm on the court. That's just always been my demeanor. But for me, it's more about just trusting myself and knowing that we just keep chipping away and trying to find a way - and then give yourself time to do that."

Among active players, only Serena Williams and Sara Errani have compiled longer streaks on red clay. Serena won 32 matches in a row on it between 2013-14, as well as 15 in a row in 2002-03, while in 2012 Errani captured 16 straight. Today's result pushes Barty ahead of the 14-match career-best streaks set by Venus Williams in 2004 and Simona Halep in 2018-19.

By contrast, Kvitova has now lost nine of her last 10, and 15 of her last 20, matches against Top 10 opponents. Indeed, Barty is the only player in that echelon whom the Czech has defeated since 2019, in the 2020 Doha semifinals.

"Petra and I, we respect each other as tennis players," said Barty. "And I respect her immensely as a person. I love who she is as a person, and on the court it's more than just about the result. I think we love to compete, we love to test each other, we love to test ourselves.

"I love who she is as a person, and on the court it's more than just about the result."

- Ashleigh Barty on her rivalry with Petra Kvitova.

"I think that brings in a really healthy kind of competition and relationship on the court that at the end of the day the result doesn't always matter. I think being able to enjoy it and have a smile on your face is a massive part of why I feel the tennis is always a really good level."

Barty was able to dominate a straightforward first set against an errant Kvitova. The three-time Madrid champion got off to a poor start with two double faults in a row, and never quite recovered. Amidst Kvitova's 11 unforced errors, Barty did not put a foot wrong - aside from failing to put away a smash due to getting blinded by the sun.

Kvitova fought back in the second set. A sequence of ferocious backhand returns garnered her the first break of the Barty serve, and some brilliant serve-and-volleying underlined her commitment to getting on the front foot.

But Barty regained the momentum at the start of the decider after a flurry of Kvitova forehands went astray. Midway through the set, an unfortunate net touch from the 2019 Roland Garros champion led to Kvitova getting the break back. But Barty did not let that become a turning point, coming up with some spectacular lobs to move ahead again and ultimately seal her fourth match point.

"I think I started off particularly well, and I think Petra struggled to find the court a little bit," said Barty. "I felt like she gave me a lot of cheapies, particularly in runs of two, three, four in a game. Which is always hard to kind of readjust and tactically keep doing what you're doing, knowing that a lot of the times it was out of my hands.

"I think in the second set Petra served particularly well. I felt like she made a lot more first serves. Even the depth in the box on second serves she was able to get more one-two tennis, kind of what she likes. It was important for me to manufacture a break early in the third, just to break some momentum and try and find my way back in. 

One month ago, Badosa posted a career-best result in Charleston, scoring her first two Top 20 wins over Belinda Bencic and Barty to reach her first WTA 500 semifinal. In front of her home crowd this week, her path is repeating itself.

The World No.62 made her third semifinal of the season, fifth overall and first at 1000 level with a reprise of her Charleston result against Bencic. Badosa let an initial break lead slip in both sets, but proved more solid as each reached its climax.

"I have to be honest, I was very nervous today," said Badosa afterwards. "Because sometimes these matches are a little bit tricky when you played her two, three weeks ago and you think in your head that you have that opportunity to make a semifinals. I was quite nervous, but I'm quite happy that I could control all the nerves and I could play my game quite good."

Bencic, who was seeking her second semifinal appearance in Madrid, finished with 29 winners and 29 unforced errors - but was more prone to the latter towards the end of each set. Consecutive double faults serving at the crucial juncture of 4-4, 30-30 in the first set did not help, either.

For Badosa, the 2015 Roland Garros girls' champion, this uptick has been long-awaited. Afterwards, she credited the work she has done with coach Javier Marti, the former ATP player whom she hired after last year's US Open.

Read more: Badosa embraces patience, new coach after 2020 breakthrough

"I started working with Javi at a difficult moment, where I was not where I wanted to be," said Badosa. "The change with him was very good for me. We started working from scratch, very hard. He told me that there are no secrets, that it is just working hard and one day I will be rewarded. I think this time has come.

"In 2015, I was a girl who played the ball very well but was a bit unconscious because she did not know that she was supposed to be a professional. That hurt me more than it helped me, because I won a victory without having worked so hard. It was a lot of euphoria and I thought it was going to be easier than it really is. That is not how it works. It is a day-to-day job, tennis is hard work."

Badosa, who kissed the clay of the Arantxa Sánchez Stadium after her win, will now have the chance to reprise both of her big Charleston upsets against Barty, whom she defeated 6-4, 6-3 in the quarterfinals in South Carolina. She's taking nothing for granted, though.

"I expect a completely different match," Badosa said. "She's the No.1 in the world. Now she knows me. No. 1 in the world, they don't like to make mistakes two times in a row, so for sure I expect a tough match and completely different to Charleston."

Badosa beats Bencic again, becomes first Spaniard in Madrid SFs: Highlights