ROME (AP) — Iga Swiatek stepped up and nobody has brought her down.

Swiatek earned the No. 1 ranking in women’s tennis by default two months ago when Ash Barty announced her immediate retirement. Add in Serena Williams’ absence for nearly a year and there were plenty of questions about who might assert themselves as the new woman to beat.

Well, since February, nobody has beaten Swiatek.

The Polish player extended her winning streak to 26 matches and reached the Italian Open semifinals after beating former U.S. Open champion Bianca Andreescu 7-6 (2), 6-0 on Friday.

Swiatek struggled to handle being a top-five player last year. Now she’s learned how to use her recent success to intimidate.

“I needed time to learn how to do that properly, how to use the streak or ranking to put pressure on my opponents,” Swiatek said. “Last year when I had (a) better ranking (than opponents), it felt like it’s something that’s pressuring me down. This time it’s totally different.”

Considering her prowess on hard courts, the often-injured Andreescu has been tossed around as a potential No. 1. But Swiatek slowly wore Andreescu down in a lengthy first set at the Foro Italico and dictated the tiebreaker by moving her opponent from side to side.

In all, Swiatek produced 27 winners to Andreescu’s 12 and converted all six of her break points.

“I feel like every match I’m playing better and better,” Swiatek said. “Even though the first set was pretty tight, I had some ups and downs, I feel like I could play well in important moments and break back anytime.

“I’m pretty happy that also the second set was more solid because it shows that I’m learning my lessons throughout the whole match.”

Swiatek’s semifinal opponent will be third-seeded Aryna Sabalenka, who rallied past Amanda Anisimova 4-6, 6-3, 6-2 for her first victory over the American in five tries.

Also advancing was recent Madrid Open champion Ons Jabeur, who rallied past Maria Sakkari, 1-6, 7-5, 6-1 for her 10th straight win. Jabeur’s semifinal opponent will be Jil Teichmann or Daria Kasatkina.

In the men’s tournament, fifth-ranked Stefanos Tsitsipas served 10 aces to defeat Jannik Sinner 7-6 (5), 6-2.

It’s the third consecutive Masters semifinal on clay for Tsitsipas, who defended his Monte Carlo Masters title last month and then was beaten by Alexander Zverev in Madrid.

Tsitsipas will face Zverev again in the Rome semifinals after the 2017 champion beat Cristian Garin 7-5, 6-2.

Later, top-ranked Novak Djokovic faced Felix Auger-Aliassime for the first time. The winner of that match will face Casper Ruud, who beat Denis Shapovalov 7-6 (7), 7-5.

Swiatek is attempting to win her fifth straight tournament and defend her title in Rome.

The last player to win more consecutive matches was Williams in 2014-15, when she had a streak of 27.

Swiatek’s run makes her a favorite to win a second French Open title when the year’s second Grand Slam gets underway in nine days. When Swiatek won at Roland Garros in 2020 she was ranked No. 54 — making her the lowest-ranked woman to win the Paris major in the Open era.

Swiatek’s recent success has also given her a comfortable 2,000-point lead in the rankings over No. 2 Barbora Krejcikova, who is out injured.

Tsitsipas kept his cool with nearly the entire crowd of 10,500 fans supporting Sinner, the Italian who is ranked 13th and considered a future Grand Slam contender.

The 20-year-old Sinner dropped to 0-12 in his career against opponents ranked in the top five.

He was treated by a physical trainer after twisting his left hip during the final point of the first set.

His body is still developing physically.

“That’s where the gap is,” Sinner said. “In terms of tennis, I’m there. Physically, I need to improve.”

There was an interruption of more than 10 minutes when Tsitsipas held his second match point because a spectator fell ill near the top of the stadium. But Tsitsipas held his nerve and won the point when play resumed by running down a drop shot and responding with a forehand winner up the line.

“It’s a tricky situation,” Tsitsipas said. “I’ve never been faced with that before.”