Soon to assume the mantle of women’s world No.1, Polish star Iga Swiatek has progressed to her fourth WTA 1000 semi-final by defeating Petra Kvitova in straight sets at the Miami Open.

After taking out tournaments in Doha and Indian Wells this year, the 20-year-old’s undefeated streak now moves to 15 in a row following Wednesday’s 6-3 6-3 victory.

Kvitova largely stayed in points in the opening exchanges and held a higher first-serve rate than her opponent, but indicative of the form Swiatek is currently in, she played with clarity and did not hesitate when opportunities presented.

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Along with winning six of eight points on Kvitova’s second serve in the first set, Swiatek converted on her sole chance at break point, claiming the crucial break in the sixth game before closing the opening set out.

After a tough service hold in the fourth game and four initial chances at break point in the second set, Swiatek made it count on her fifth attempt, spectacularly managing to move the 28th seed around the court and turn defence into attack.

Seeing the finish line, the Polish second seed grew increasingly assertive in both serve and shot selection to both secure the break and see out the match, even claiming a second break for a punctuation mark.

Swiatek will face Jessica Pegula, who is also through to the semi-finals after Paula Badosa retired from their match-up due to a viral illness.

Pegula was leading 4-1 after only 18 minutes of play when Badosa retired, having won four straight games after initially dropping her serve.

The 28-year-old has now won her last two matches in Miami via retirement after she advanced past Anhelina Kalinina in the fourth round, winning the first set 6-0.

“Of course, it’s not nice to win that way,” Pegula said. “It’s the first time I’ve ever even hit with her at all and I was really looking forward to playing because she’s been having an amazing year.”

Badosa, who was No.71 in the world rankings at this time last year, will climb to a career-best No.3 when the rankings are updated on Monday. She would have gone to No.2 had she beaten Pegula.

Badosa said she woke up on Monday not feeling well and wasn’t even sure she could play that day in a fourth-round against Linda Fruhvirtova. Badosa battled through, winning that match 6-2 6-3 but was clearly not herself on Wednesday.

“She’s an incredible competitor,” Pegula said. “I think we all saw that last round where she clearly wasn’t feeling well and she was able to tough it out.

“I admire that a lot and hopefully next time we can both play when we’re healthy and feeling good and have a great match.”

If Pegula defeats Swiatek in the semi-final, it would make for her maiden WTA 1000 final appearance.

with AP