There were contrasting outcomes for seeded players taking on unseeded American teenagers in the second round of the Internazionali BNL d'Italia.

No.5 seed Elina Svitolina survived a barrage of power to turn around her match with Amanda Anisimova 2-6, 6-3, 6-4, but Coco Gauff held off a fightback from No.17 seed Maria Sakkari to progress 6-1, 1-6, 6-1.

Svitolina will next face No.12 seed Garbiñe Muguruza, who overcame nine double faults and came from a double break down in the third set to quell qualifier Bernarda Pera 2-6, 6-0, 7-5. Gauff will take on No.5 seed Aryna Sabalenka after the Madrid champion triumphed in an extreme stylistic contrast over Sara Sorribes Tormo 7-5, 6-1.

Despite a slow start to fall behind 0-2, Anisimova dominated the opening set against two-time Rome champion Svitolina. The 19-year-old dropped just eight points in the next seven games, repeatedly hammering clean return winners as she built a 6-2, 1-0 lead.

Anisimova was seeking her first Top 10 win since Doha 2020, where she defeated Svitolina in the second round to level the head-to-head between the pair. But the Ukrainian had other ideas. Facing a break point to fall behind 0-2 in the second set, she found a backhand winner of her own - and the comeback was on.

The second set would see six breaks of serve as both players' accuracy ebbed and flowed. But that kind of scrappy battle is where Svitolina thrives, and she weathered the ups and downs to break Anisimova for the set as the teenager sent a pair of groundstrokes long.

The efficiency of Svitolina's serve is often the key to her matches, and Anisimova's ability to swat it away had been crucial to her early lead. The third set saw Svitolina's best serving stats of the day, landing 66% of her first serves compared to 59% in the first set. Having won only 22% of her second serve points in the opener, Svitolina also managed to protect it better in the decider, capturing 75% of those points.

Having given Anisimova a taste of her own medicine to break for 2-0, Svitolina remained largely in control throughout the rest of the set. A wobble as she failed to serve out the match was swiftly put behind her. As in the second set, she broke to seal the win with a combination of aggressive forehands and Anisimova errors.

Gauff solves Sakkari at third attempt

Sakkari had hitherto been something of a nemesis for Gauff. The Greek had won both of their previous encounters, at the Western & Southern Open last year and in Abu Dhabi this year, with little fuss.

But Gauff, 17, struck a fine balance between offence and defence to emerge with a rare triple-breadstick scoreline. Each set hinged on a handful of epic games, following which the winner ran away with the momentum.

In the first set, Gauff took her third break point with a beautiful dropshot to lead 3-1, and then staved off a break-back point to lead 4-1 in a game that ended controversially. After disagreeing with umpire Jenny Zhang's decision to award the final point to Gauff, Sakkari took her frustration out on her racquet during the changeover, and fell away in the rest of the set.

But having been broken at the start of the second set, Sakkari's fighting spirit shone through in a marathon second game. The 25-year-old survived five deuces to get the break back, and thereafter played with verve and confidence to level the score.

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2021 Rome

It was Gauff's turn to show grit as the decider got under way. She came through a five-deuce tussle, saving one break point, to hold in the first game, then took her fourth break point to move up 2-0 as Sakkari sent a backhand wide.

Gauff took charge after that, moving up 5-0 in the blink of an eye. A third ace brought up her first match point, and she sealed her second as another Sakkari forehand drifted wide.

Muguruza shows mettle in comeback

In an oscillating encounter, Muguruza's form swung back and forth before overcoming Pera.

The Spaniard, who withdrew from Madrid last week with a left thigh injury, committed three double faults in the opening game, five in the first set and nine in total. Pera also started slowly with two double faults, but once she hit her stride dominated the opener. The American won 16 of the first set's last 20 minutes against a barely-competitive Muguruza.

After an off-court medical timeout, the Dubai champion struck back ruthlessly. With her groundstrokes clicking, she raced through a second-set bagel. But Pera took charge again in the third set. The American played her best tennis of the day to power to a 4-1 double-break lead, with her forehand in particular doing damage.

Pera has struggled to close out matches of late though, having dropped eight of her 12 three-setters in 2021. Those include losses from 5-1 (and match point) up in the decider to Sara Sorribes Tormo in Miami, 6-4, 4-2 up to Alizé Cornet in Charleston, and 4-2 up in the final set to Veronika Kudermetova in Istanbul.

Errors duly crept into the Pera game, as well as three double faults to give up the second break, and Muguruza seized her lifeline. The former World No.1's fight was evident in a number of superb defensive points, and she would win six of the last seven games.

"I don't think it was a great match, but we fought very well and I'm pretty happy with my attitude," said Muguruza. "It wasn't my best day, but I stood there and fought hard. I tried just to stay calm and basically put the ball in, because in the first set I was doing so many mistakes and giving her so many opportunities. In the second set it was the opposite. In the third set it was a combination of errors."

Sabalenka and Sorribes Tormo deliver extreme stylistic contrast

A match between Sabalenka and Sorribes Tormo is Exhibit A that tennis is a sport that can be played in vastly different ways. Indeed, their previous encounter last year in Ostrava encapsulated this: Sorribes Tormo won the first 10 games, then Sabalenka won the next 12 for a 0-6, 6-4, 6-0 victory. It was a contest that set both players on an upwards trajectory ever since.

Here, there were fewer dramatic fluctuations - though the final stats were still remarkable. The Belarusian, unleashing her power in every rally, finished with an astonishing 53 winners to 36 unforced errors. Sorribes Tormo, defending relentlessly, was watertight with three winners and only five unforced errors.

The Spaniard had won the longest WTA-level match in nearly a decade on Monday, a three-hour, 51-minute epic over Camila Giorgi that was also the sixth-longest match of the Open Era. She brought much of that spirit to the contest against Sabalenka, and the pair's contrasting styles made for several thrilling rallies.

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The key numbers for Sabalenka were the 12 break points she saved out of 13 faced. The bulk of these came in consecutive service games midway through the second set, during which the new World No.4 was dragged through a total of 12 deuces.

But her ability to find the focus she needs to come through those tussles has been crucial to her consistent level over the past eight months. Sabalenka won both of those games, then powered through the finishing line with six forehand winners in the last two games.

"It was a tough match and not the best tennis from me," said Sabalenka. "But she was doing all the right things - moving very well, putting all the balls back. She made me run a lot and move a lot so it was tough from the beginning. I just kept saying to myself, Keep going, keep moving, try to go through the ball. I was thinking about the movement on the court and trying to get a rhythm in the legs, and I think I did that very well in the second set."