ROME, Italy -- World No.1 Iga Swiatek survived a bruising test to overcome former No.1 Victoria Azarenka 6-4, 6-1 to advance to the quarterfinals of the Internazionali BNL d'Italia. The victory extended Swiatek's winning streak to 25 matches, the longest since Serena Williams ran off 27 straight wins in 2015. The victory sets up a marquee matchup Friday against 2019 US Open champion Bianca Andreescu. 

While the score line appears perfunctory, Swiatek found herself under constant pressure from Azarenka's return game. The 20-year-old needed 79 minutes to complete a comeback from a double-break, at 0-3, in the opening set. Azarenka held at least one break point in each of Swiatek's service games in the opener, generating a total of 11 break points. 

"I didn't start well, and everybody could see that," Swiatek told reporters. "I'm really happy with the way I reacted and how I improved in the first set. Also how different the second set looked to the first one because I could really reset and really change the way I played. That's the most positive thing for me."

But in the key game of the first set, Swiatek came through a seven-deuce game, wiping out three break chances, to hold for a 4-3 lead. That hold was a part of a five-game run for Swiatek, but Azarenka's fight never wavered. With Swiatek serving for the set at 5-3, the former No.1 wiped out four set points and broke to get back on serve. 

Swiatek kept her cool. By now, the Pole had leveled up her tour-best return game, and she broke Azarenka on her fifth set point to finally seal the set. Swiatek continued to dominate on return through the second set, breaking Azarenka four more times to close the match and book her spot in a fifth straight quarterfinal. 

Stat of the match: Under pressure throughout the lengthy opening set, Swiatek was forced to play 74 points on her serve. In contrast, Azarenka played just 30. But Swiatek's ability to save eight of 11 break points while converting four of the five break points she earned, flipped the script on an otherwise strong first set from Azarenka.

When the dust finally settled on Court Centrale, Swiatek won 12 of the last 14 games of the match. Swiatek finished with 34 winners to 39 unforced errors, while Azarenka fired 18 winners to 31 unforced errors. 

Rome: Swiatek reels in Azarenka for 25th consecutive win

Andreescu books her biggest quarterfinal on clay

Three tournaments into her comeback, Andreescu has reached her first WTA 1000 quarterfinal in 14 months, defeating qualifier Petra Martic 6-4, 6-4 in 1 hour and 43 minutes in the Round of 16.

Highlights: Andreescu d. Martic

The 21-year-old Canadian returned to action in Stuttgart last month following a six-month mental health hiatus, and is making her debut in Rome. In a first-time encounter with last year's semifinalist Martic, she dealt with the tough challenge of an experienced clay-court expert with impressive sharpness.

No.90-ranked Andreescu's last appearance in a WTA quarterfinal was also her only previous run to the last eight on clay, at the WTA 250 in Strasbourg last year. This result marks her first WTA 1000 quarterfinal since reaching the 2021 Miami final.

By the numbers: In a clash between two strong servers, the stat sheet illustrates Andreescu's superiority in this key area and in crucial moments. The former US Open champion landed 72% of her first serves compared to Martic's 50%, and saved six of the seven break points she faced while converting three out of four on Martic's serve.

The first of the latter came at 4-4 in the first set. With the match on a knife-edge, Andreescu seized control, swatting away a drive volley to move ahead. Martic began to cough up double faults as the second set got under way, and Andreescu continued to take advantage, slamming a forehand winner to break for 2-1.

Martic's wide repertoire of shots garnered the Croat plenty of highlights, and a flurry of form saw her break back and hold two points for a 4-2 lead. But the World No.47 squandered both, and continued to be afflicted by double faults, tallying six in the second set alone.

The fifth of those handed the break back to Andreescu, who successfully served out the win by putting away a volley on her third match point.

Sabalenka, Teichmann advance to last eight

Earlier, No.3 seed Aryna Sabalenka captured her third straight win over No.13 seed Jessica Pegula 6-1, 6-4 in a dominant power display to reach the Rome quarterfinals for the first time.

Highlights: Sabalenka d. Pegula | Teichmann d. Rybakina

Sabalenka extended her overall head-to-head against the American to 3-1, with her trio of victories all coming in straight sets on clay. Pegula, who reached her first WTA 1000 final last week in Madrid, managed to get back on serve after trailing 5-2 in the second set, but conceded defeat with a double fault.

However, Jil Teichmann managed to continue her strong form from Madrid, where she was a semifinalist. The swashbuckling Swiss, at a career-high of No.29, pulled off her second three-set upset on Pietrangeli of a Top 20 player, defeating Elena Rybakina 6-7(3), 6-3, 7-5 in 3 hours and 2 minutes.

Variety in her game and life driving Jil Teichmann to new heights

It is the second tournament in a row that Teichmann has taken out the Kazakh at the same stage, though her marathon Rome win was somewhat harder work than her 6-3, 6-1 victory in Madrid. The result is Teichmann's 13th career Top 20 win, with her 12th coming one day previously on the same court over Karolina Pliskova.