An all-American third round is on tap at the French Open thanks to wins by Serena Williams and Danielle Collins on Wednesday.
Williams, seeded No.7, playing her second Romanian foe in as many matches, was pushed the distance in a 6-3, 5-7, 6-1 match against former Top 20 player Mihaela Buzarnescu on Court Philippe-Chatrier.
After losing a 5-2 lead and later saving two set points in the opening set of her in her first-round win over Irina-Camelia Begu on Monday night, Williams told reporters she was much happier with her serving performance in round two despite being taken in the distance.
In the match overall, Williams won 75 percent of the points played behind her first serve and saved five of the seven break points she faced.
To take a one-set lead, she also lost just three points in five service games.
"I felt it was pretty good today," Williams said of her serve. "But I've been practicing my serve a lot. I've been playing in practice unbelievable on my serve. The other night was, wow. I'm glad it came better today.
"My coach told me it's good that I'm doing it well in practice because eventually it will be good in the match."
After just one break decided the opening set, Buzarnescu showed the kind of tennis that took her to the world's Top 20 just three years ago before she was set back by injury. The Romanian saved seven of the eight break points she faced in the second set, including a hold from 15-40 at 5-5, and broke serve for the second time to push the contest to a third - capping a lengthy rally with a scintillating backhand winner.
However, her momentum could not carry over early into the third: after Buzarnescu double-faulted to lose serve in the first game, Williams hardly looked back and built a 4-0 lead.
"I had some really good chances in the second set to win that if I would have won just one point here or there, like four or five times. It would have been a different second set," Williams said.
"I know going into the third I just had zero in on those one important points. If I could just take those, it would be an easier time for me."
It was nonetheless an encouraging result for the 33-year-old former world No.20, where she also had a brief window of opportunity to close the gap in the final set.
After saving a break point to get on the board, she had a look at 30-30 and deuce in the sixth game to create break point opportunities, but Williams ultimately came through the hold and won the last six points to seal victory.
In all, the two players were evenly matched off the ground: Williams totaled 26 winners to 27 unforced errors, while Buzarnescu ended with 25 winners to 28 unforced. However, Buzarnescu also racked up seven double faults without an ace, while Williams served five aces and two double faults.
"It was like a dream for a long time to play against her, because since I was young I was following her and her sister," Buzarnescu, now ranked World No.174 and entered in Paris on a protected ranking, said in defeat. "It was always like, let's say, like a goal to play against such a legend.
"Before my match I really, like, put this [aside] and said, 'It's a match, so I have to play against a player as any other player and I have to focus on my game and just try my best and see the result at the end.'
"I just think that I had a good match today. It's always tough to play against a player as her with such a tough serve and very powerful shots. I was really a bit disappointed at the end of the match. I couldn't finish some of the points that could have given me more chances in the final set."
Collins, a quarterfinalist in 2020, was one of the first winners on Wednesday. She dropped just two games against Ukrainian qualifier Anhelina Kalinina, 6-0, 6-2, to put an end to the qualifier's 14-match winning streak.
The two Americans met just five months ago for the first time, with Williams winning in a match tiebreak the quarterfinals of the Yarra Valley Classic, 6-2, 4-6, 10-6, with the shortened match format brought on by a change in schedule.
"She's been playing well," Williams said. "I played her in Australia actually. She plays well, especially when it's time to play, which is I guess all the time. She's also a really awesome person off the court.
"I love seeing her in the locker room. Ideally, it would be great if we didn't have to play each other, because I always want her to do super well."
Joining the American duo in the third round is No.33 seed Paula Badosa, who needed just 52 minutes to beat Montenegro's Danka Kovinic, 6-2, 6-0. Badosa, a former junior champion in Paris back in 2015, will bid for a second-straight appearance in the second week against Ana Bogdan.