PARIS — Naomi Osaka is grinding her way through the French Open the hard way.
To cling onto her quest for a third consecutive Grand Slam title, the top-ranked Osaka has twice had to rally from first-set woes.
The latest opponent was the former No. 1 Victoria Azarenka, and Osaka survived, 4-6, 7-5, 6-3, on Thursday in a second-round match with superb shotmaking.
Osaka, the reigning United States Open and Australian Open champion from Japan, surprisingly lost her first set, 6-0, in the first round, and again started poorly.
Azarenka, now ranked No. 43 and without a major title since winning the Australian Open in 2012 and 2013, raced to a 4-0 lead on Suzanne Lenglen Court and kept Osaka under constant pressure.
Osaka considered herself unfortunate to be drawn against Azarenka, and the powerful, accurate tennis produced by the 29-year-old Belarusian playing in her 12th French Open showed why.
Broken by a backhand volley at the net from Azarenka in the fifth game of the second set, Osaka seemed to be in deep trouble. But, as she did in beating first-round opponent Anna Karolina Schmiedlova, Osaka proved her resilience.
The eighth game of the second set was pivotal. After saving two break points, Azarenka double-faulted. Osaka leveled at 4-4, and the momentum started to shift. It was the seventh break point Azarenka had faced in the set, and the first she had failed to save.
But Azarenka still saved three set points before Osaka finally leveled the match with a backhand cross-court winner.
The third set was packed with drama, too, with Osaka finally taming Azarenka with her third match point, when her combative opponent hit long.
In the third round, Osaka will play Katerina Siniakova, ranked No. 42. Siniakova dispatched 29th-seeded Maria Sakkari, 7-6 (5), 6-7 (8), 6-3, in a 3-hour, 10-minute match.
Serena Williams advanced to the third round by beating Kurumi Nara, 6-3, 6-2, on Philippe Chatrier Court.
Nara, a Japanese player and ranked No. 238, reached the main draw at Roland Garros via the qualifying tournament. The gulf between her and Williams, a 23-time major champion, was quickly apparent.
Williams faced no break points, served 10 aces and made 36 winners. She will next play Sofia Kenin, ranked No. 35.
Dominic Thiem, the No. 4 seed in the men’s draw, overcame some trickery from Alexander Bublik of Kazakhstan to advance to the third round with a 6-3, 6-7 (6), 6-3, 7-5 victory.
Bublik surprised Thiem with an underhand serve in the first set and frustrated him with a series of drop shots, spins and volleys.
But Thiem, last year’s finalist at Roland Garros, recovered from a break of serve in the fourth set and then gave Bublik a taste of his own medicine on his first match point, producing a well-disguised — and successful — drop shot.
Thiem will next face Pablo Cuevas, another master of trick shots. Cuevas was leading, 7-6 (3), 6-3, 2-1, when Kyle Edmund retired from their match because of a left knee injury.
In a career already full of milestones, Novak Djokovic passed another one in reaching the third round of the French Open: His young son watched him play at the tournament for the first time.
Luckily for Stefan Djokovic, his top-ranked father beat Henri Laaksonen, 6-1, 6-4, 6-3.
Novak Djokovic said, “it’s incredible that he has the patience for 1 hour and 30 minutes.”
Djokovic’s next opponent, 147th-ranked Salvatore Caruso of Italy, reached the main draw via the qualifying tournament.
The American teenager Amanda Anisimova pulled off an upset, defeating 11th-ranked Aryna Sabalenka, 6-4, 6-2
Anisimova, 17, is proving to be a jinx at Grand Slam tournaments for Sabalenka, who lost to Anisimova in the third round of the Australian Open in January.
Anisimova, ranked No. 51, is making only her second appearance at Roland Garros. She lost in the first round in 2017.
Another teenager, Iga Swiatek, who turns 18 on Friday, knocked out 16th-seeded Wang Qiang, 6-3, 6-0, in under an hour to reach the third round of a Grand Slam tournament for the first time.