Jannik Sinner and Carlos Alcaraz enter the 2025 US Open semi-finals with the world No 1 ranking hanging in the balance. The pair are on course to meet in a third consecutive Grand Slam final, and the outcome at Flushing Meadows will determine which player holds the top spot.

In the last four, Sinner faces world No 27 Felix Auger-Aliassime while Alcaraz takes on seventh seed and 24-time Grand Slam champion Novak Djokovic. Sinner has occupied the ATP world No 1 position for 65 consecutive weeks since overtaking Djokovic to reach the top in June 2024 following last year’s French Open. Alcaraz became the youngest world No 1 in ATP history after winning his first Grand Slam at the 2022 US Open at the age of 19 years and four months. He has spent 36 weeks as the sport’s highest-ranked player, with his most recent spell on top ending in September 2023.

In the final tournament before the US Open, Alcaraz won the Cincinnati Masters after Sinner was forced to retire due to illness in the first set of the pair’s meeting in the final. Alcaraz, listed as world No 2 at the start of the US Open, began the event on 9,590 points, 1,890 points behind Sinner, who began on 11,480.

Because Sinner was defending 2,000 points as the reigning US Open champion while Alcaraz was defending just 50 points after a second round loss to Botic van de Zandschulp last year, the results at this event could flip the rankings. Heading into the semi-finals, Alcaraz had increased his total by 750 to 10,340 and held the No 1 spot in the Live ATP Rankings. Sinner was 1,200 points down from his pre-tournament total and sat 60 points behind on 10,280.

That leaves clear scenarios. If Sinner loses to Auger-Aliassime, Alcaraz will become world No 1 regardless of his own later results. If Alcaraz loses to Djokovic, Sinner can secure his position by reaching the final. If both reach the final, Alcaraz’s 60-point lead means the winner takes the title and the No 1 ranking.

Projected points outcomes:
Sinner — Wins the title: 11,480 points; Loses in the final: 10,780 points; Loses in the semi-finals: 10,280 points.
Alcaraz — Wins the title: 11,540 points; Loses in the final: 10,840 points; Loses in the semi-finals: 10,340 points.

Novak Djokovic arrives at the US Open semifinal with a familiar mix of experience and uncertainty. He has reached the semifinals at each of the three majors in 2025 but has not taken a set in any of those matches. At the Australian Open he retired after the first set against Alexander Zverev; at Wimbledon he lost in straight sets to Jannik Sinner after not being fully fit. At Roland Garros he was at full strength yet still failed to win a set.

Health is the central question. Djokovic has called the trainer on a couple of occasions at this Open, but those issues proved temporary. He survived a late, difficult four-set match against Taylor Fritz and, while he looked weary at times, he was not pushed to the brink. A two-day recovery window appears feasible. “I definitely am not going with a white flag on the court,” Djokovic says. “The next couple of days is really key for me to really get my body in shape and ready to battle five sets if it’s needed.” He added, “Would love to be fit enough to play and to play, you know, potentially five sets with Carlos. I know that my best tennis is going to be required, but I’d rise to the occasion.”

Opposite him stands Carlos Alcaraz, who has carried exceptional form into New York. He has won 43 of his last 45 matches, captured five titles on three surfaces since the spring, and has yet to drop a set at this tournament. After beating Jiri Lehecka, Alcaraz reflected, “I think today I just played a really—or almost perfect match, I would say. So playing a quarterfinal of a Grand Slam, I’m feeling that way. It seems like, OK, just two more steps to do, and let’s see what happens.” He also noted of Djokovic, “We all know Novak’s game. It doesn’t matter that he has been out of the tour since Wimbledon. Playing great matches here. I know he’s hungry. I know his ambition for more, so let’s see.”

Head-to-head history gives Djokovic reason for confidence: he leads 5-3 overall and 3-0 on hard courts, including a four-set win in the Australian Open quarterfinal this year. Still, Alcaraz’s recent dominance and fitness present a stern test. Djokovic admitted the uncertainty plainly: “It’s just that I’m not really sure how the body is going to feel in the next few days,” he said. “But I’m going to do my very best with my team to be fit for that. There’s going to be a lot of running involved, that’s for sure.”

Aryna Sabalenka’s ascent to the top of the WTA is as much a family story as it is a sporting one. The multiple-time Grand Slam champion and former world No 1 in singles and doubles developed the foundations of her career with strong backing from her parents, particularly her late father, Sergey, and her mother, Yulia.

Sport was a part of Sergey’s life from a young age. He had hoped for a career in ice hockey until a severe car crash at 19 changed his path. Despite that setback, Sergey remained passionate about sport and introduced a six-year-old Sabalenka to tennis in Minsk. “One day, my dad was just driving me somewhere in the car, and on the way, he saw tennis courts,” said Sabalenka, speaking in a 2017 interview to First Post. “So he took me to the courts. I really liked it and enjoyed it, and that’s how it was. That’s how it started.”

Sergey stayed a central figure in her early career and was present as she claimed back-to-back WTA 1000 titles at the Wuhan Open in 2018 and 2019 and lifted the 2019 US Open women’s doubles trophy. He died in November 2019 at age 43, reportedly of meningitis. In the Netflix series Break Point, Sabalenka reflected on the ambitions they shared: “I lost my father four years ago. We had one dream, that before [I turn] 25, I will win a couple of Grand Slams.

“When he passed away, I started thinking too much about it. Now I’m 24 and there is zero in my pocket.”

Sabalenka later achieved the Grand Slam success she and her father had hoped for, taking her first major singles title at the 2023 Australian Open and adding further major victories, including the 2024 Australian Open and the US Open.

Yulia has kept a low profile but publicly celebrated her daughter’s milestones. After the 2023 Australian Open, she wrote: “We are proud of you” and “Just my Princess”. When Sabalenka defended the title in 2024, Yulia posted: “Twins — I want at least triplets!!! And we need to diversify the collection somehow.”