The 54-minute second set: the test Sabalenka needed before her US Open three-peat push

The number that mattered most after Aryna Sabalenka left the court in the US Open third round was 54. She had just beaten Ekaterina Rakhimova 6-3, 7-5, but the second set lasted longer than her entire previous match in the tournament. For a two-time defending champion chasing a third straight title in New York, that tense stretch is worth more than an ordinary victory. The US Open is the last Grand Slam of the season, offering 2,000 ranking points to the champion. Sabalenka arrived as the No. 1 seed and champion of the past two years, but she also faced the pressure of defending those 2,000 points. Her edge is consistency and comfort on hard courts, where she has already lifted the trophy twice. History, however, reminds her that no woman has completed a three-peat in New York since Serena Williams. Rakhimova did not come to the third round to fill out the draw. She returned serve deeply, moved well and refused to be pushed off the baseline. Sabalenka took the first set 6-3 more comfortably, but the second set changed. Rakhimova stepped closer to the baseline, neutralized many powerful serves and made the defending champion work harder for every point. The key was not the length of the set, but how Sabalenka stayed patient during difficult moments. Casual viewers remember winning shots. Those who follow Sabalenka closely read the rhythm of the match. She did not try to finish every point with one winner. She accepted longer rallies, moved more and waited for the opponent's errors. That is the mark of a mature champion who understands the US Open is not decided by power alone, but by the ability to handle momentum swings. Sabalenka praised Rakhimova after the match, saying the opponent played at a very high level and forced her to find different solutions. Her words sounded genuine when placed next to the 54-minute stat. Rakhimova may not have big titles, but she turned the third-round match into a tactical test. Sabalenka needed that test before facing top seeds in the following rounds. The fourth round will likely bring Diana Shnaider, the No. 15 seed, or Taylor Townsend. Both left-handers can create problems with fast play and spin. Shnaider has a strong serve, while Townsend often comes to the net and uses variety. If Sabalenka keeps the focus she showed in the second set against Rakhimova, she remains the clear favorite. But if she grows impatient again, either opponent is good enough to cause an upset. Another storyline on the same day was Sorana Cirstea. The 36-year-old Romanian defeated Jasmine Paolini, the No. 19 seed, to advance deeper. Cirstea has mentioned the possibility of retirement after this season, yet she played with the hunger of someone who does not want to leave early. Beating a top-20 player is a reminder that experience and calm still matter at a Grand Slam. Venus and Serena Williams are also part of the US Open narrative this year with their doubles return. Their match is scheduled for Friday night, a nostalgic moment for New York fans. Their presence highlights a reality: American tennis is still searching for the next great generation. Experts expect more from young players such as Shnaider or Townsend, but the transition is not complete. For Sabalenka, the win over Rakhimova showed that she understands her goal. She does not talk about defending points or staying No. 1. She talks about improving from match to match, respecting opponents and being ready for long sets. At 26, she is in the prime of her career and knows opportunities to write history do not come often. People who only looked at the 6-3, 7-5 scoreline may think Sabalenka is still too strong for everyone else. A closer look at the rhythm tells a different story. The 54-minute second set was a message. Future opponents will gain confidence knowing that Sabalenka can be pushed into uncomfortable positions. Top players in the later rounds will not ignore that signal. The irony is that the closer Sabalenka gets to a three-peat, the heavier the pressure becomes. She is not only fighting opponents on the court; she is also answering questions about history every day. Serena Williams was the last woman to achieve this, and comparisons to a legend carry their own weight. Sabalenka does not need to answer all those questions this week. She only needs to keep her rhythm, win match by match and let the numbers speak. From the perspective of someone who has watched many US Opens, the match against Rakhimova may be the most valuable moment in Sabalenka's campaign. A too-easy third-round win could make her overconfident. A long match where she has to find a way through resistance prepares her better for what lies ahead. Sabalenka was not perfect, but she showed adaptability. For a champion chasing a third straight major title, that is what matters most. The big question now is not whether Sabalenka can win the title. It is how she will enter the next big match after such a difficult evening. If she treats those 54 minutes as a lesson, the whole draw should beware. If she dismisses it as just a hard day, pressure will be waiting for her. Sabalenka knows better than anyone that the US Open does not forgive a loss of focus. For now, she is still keeping the beat very well.