The top two seeds at the China Open both overcame tough opposition to book their places in the third round. No.1 Aryna Sabalenka had to erase deficits in both sets to edge qualifier Katie Boulter 7-5, 7-6(2), while No.2 Iga Swiatek pulled away from Varvara Gracheva 6-4, 6-1 after a close opener.

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Sabalenka had defeated Boulter both previous times they had played, but neither match had been straightforward -- particularly a 4-6, 6-3, 6-3 battle in the second round of Wimbledon 2021. The Briton once again demonstrated her ability to push Sabalenka hard, serving for both sets at 5-4 before ultimately falling in 2 hours and 32 minutes.

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Swiatek had not faced Gracheva since their junior days, a 6-3, 6-2 win on the clay of Milan in 2017, but the No.47-ranked Frenchwoman has posted her best career results this year. Though her form has tailed off following the Austin final and back-to-back fourth-round runs at Indian Wells and Miami, Gracheva was able to test Swiatek in the first set before the Polish player rolled in the second.

How Sabalenka escaped Boulter: Both players stayed committed to aggressive tennis, firing 34 winners each. Though Sabalenka's first strike had the edge, Boulter's forehand on the run delivered a number of highlights. Opportunities were plentiful -- the match saw 24 combined break points, 12 apiece for each player, but ultimately it was Sabalenka who was able to convert three times to Boulter's two.

Boulter was able to withstand the World No.1's return pressure early on. Sabalenka had break points in each of the Nottingham champion's first three games, but could not break through. In a remarkable effort in the fourth game, Boulter saved six break points to keep Sabalenka at bay.

Boulter, the World No.56, was rewarded when she became the first player to break. As Sabalenka's frustrations grew, Boulter extended her lead to 5-3 and served for the opening set at 5-4. But an error-strewn game ensued to hand Sabalenka her first break of the match. Sabalenka inched ahead by saving eight break points in the 5-5 game to lead 6-5 and closed the set by breaking Boulter for a second time, with the latter netting consecutive backhands on the final two points of the set.

Undeterred by the manner of losing the opener, Boulter continued to put up stern resistance in the second set. She found an off forehand winner to break for 5-4, only to be denied in the next game by some smart Sabalenka returns deep at Boulter's feet. The Australian Open champion went on to dominate the ensuing tiebreak.

What's next for Sabalenka: A third-round meeting with No.36-ranked Jasmine Paolini, who leads their head-to-head 2-1. The Italian triumphed in three-setters in the first round of the 2017 Ilkley ITF W100 event and the second round of Indian Wells 2022. In between, Sabalenka was a straight-sets victor in the first round of Linz 2020.

Sabalenka on her win: "In the key moments I played a little bit better than her. I think it was all about the last games in each set. I mean, she had the opportunity. I'm super happy that I didn't give her easily those sets. I was keep fighting, keep trying."

Sabalenka on facing Paolini next: "Last year Indian Wells, I wasn't [in] my best shape. I was struggling a lot with a lot of different things. I would say it wasn't me last year at Indian Wells. I'm really happy to have this opportunity for revenge."

How Swiatek defeated Gracheva: Two superb winners in the first three points from Gracheva were a statement of her aggressive intent. But while the 23-year-old delivered her share of highlights, four-time major champion Swiatek was able to sustain her top level throughout the whole match.

Highlights: Swiatek d. Gracheva

Gracheva's best passage of play came in the first set, when she cut Swiatek's 4-1 double-break lead to 4-3. However, Swiatek steadied herself with some superb forehands to preserve her insurance break and close out the set.

The former World No.1 battled through a five-deuce game at the start of the second set to break ahead of a 90-minute rain delay. On resumption, Gracheva's form of the first set had disappeared. Her unforced error tally mounted to 24, while Swiatek repeatedly teed off on returns to race towards the finishing line.

What's next for Swiatek: A rare meeting against a Polish compatriot as she takes on Australian Open semifinalist Magda Linette. Swiatek has not faced Linette before. She has played a fellow Pole only three times at any pro level before. Her only tour-level meeting with a countrywoman was in the first round of Warsaw 2022, when she defeated Magdalena Frech 6-1, 6-2.