The world No. 1’s persistent knee problem removes one of New York’s leading title favourites, while another setback for Britain’s Jack Draper underlines the physical toll of the modern tennis calendar.

The US Open has suffered two significant blows on the eve of the final Grand Slam of the season, with world No. 1 Jannik Sinner and Britain’s Jack Draper withdrawing because of injury.

Sinner confirmed on Friday that a persistent problem with his right knee had not improved sufficiently for him to compete at Flushing Meadows, ending hopes that the Italian could renew his increasingly defining rivalry with Carlos Alcaraz on one of tennis’s biggest stages. The 24-year-old had not played a competitive match since successfully defending his Wimbledon title against Alexander Zverev on July 12.

The withdrawal is particularly striking because Sinner had been enjoying an extraordinary season. He arrives at this enforced break with a 44-3 record in 2026, having collected six titles, including Indian Wells, Miami, Monte Carlo, Madrid, Rome and Wimbledon. His victory over Zverev at the All England Club gave him a fifth Grand Slam title and a second consecutive Wimbledon crown.

But the knee issue has interrupted that momentum at the worst possible moment.

Sinner first withdrew from Montreal as he prioritised his health following Wimbledon, and the problem subsequently kept him out of Cincinnati. When he announced his Cincinnati withdrawal on August 9, he said the right knee had continued to bother him despite work with his medical team and that his immediate focus was on becoming fit for the US Open.

That recovery has not progressed quickly enough.

After returning to the practice court in Monte Carlo this week, Sinner and his medical team concluded that he required more time before returning to competition. He described the decision to miss New York as difficult and said he was particularly disappointed given his affection for the tournament and its atmosphere.

His absence fundamentally changes the complexion of the men’s draw.

Sinner won the US Open in 2024 and returned to the final in 2025, where he was beaten by Alcaraz. With the Italian now missing, the Spaniard becomes the highest-ranked player competing in New York and arguably the clearest favourite — although Alcaraz is himself returning from a four-month injury absence caused by a right wrist problem.

The timing creates one of the most unpredictable US Opens of recent years.

Sinner and Alcaraz have dominated much of the men’s game during the post-Big Three era, repeatedly meeting at the sport’s biggest events and forcing the rest of the field to chase an increasingly formidable standard. Removing one half of that rivalry gives Alexander Zverev, Novak Djokovic and several younger contenders a significantly different route toward the trophy.

Zverev, currently ranked No. 3, will see another opportunity to add to the maiden Grand Slam title he captured at Roland Garros this year. Five-time major champion Djokovic remains among the leading contenders, while Americans Ben Shelton and Taylor Fritz will attempt to end the United States’ long wait for a men’s singles Grand Slam champion.

For Sinner, the withdrawal also interrupts what had become one of the strongest seasons of his career.

At Wimbledon, he recovered from losing the opening set to Zverev to win 6-7(7), 7-6(2), 6-3, 6-4, becoming only the 10th man to successfully defend the Wimbledon singles title. The triumph appeared to confirm his position at the top of men’s tennis after a year in which his consistency across surfaces had been exceptional.

Instead of arriving in New York as one of the tournament’s central attractions, however, Sinner will now enter a rehabilitation period with his longer-term fitness taking priority over another immediate major title.

The same underlying concern — the increasingly unforgiving physical demands of elite tennis — surrounds Draper’s withdrawal.

The 24-year-old Briton has endured a particularly difficult period with injuries. After climbing to a career-high world No. 4 in 2025, Draper suffered a bone problem in his left arm that effectively ended that season. His difficulties continued into 2026, with further arm trouble and a knee injury severely restricting his schedule. He is now ranked outside the world’s top 100 after spending much of the year attempting to return to full fitness.

Draper had already been forced to withdraw from Wimbledon in June because of his arm. At the time, he described missing his home Grand Slam as one of the most painful moments of his career. He had managed just a handful of ATP events this season, although an Eastbourne semifinal shortly before Wimbledon had briefly suggested his recovery was gaining momentum.

He subsequently returned to competition during the North American hard-court swing but suffered early defeats in Montreal and Cincinnati. The Lawn Tennis Association did not initially specify the reason for his US Open withdrawal, although reports indicated that the long-running left arm problem was again responsible.

His absence is particularly unfortunate given his history in New York.

Draper produced his breakthrough Grand Slam performance at the 2024 US Open, reaching the semifinals before losing to Sinner in straight sets. That run established him as one of Britain’s most promising successors to Andy Murray and helped propel him toward the upper reaches of the rankings.

Injury has since prevented him from building consistently on that progress.

The withdrawals of Sinner and Draper consequently reopen a wider debate within professional tennis about the physical demands placed on leading players. The modern season stretches across continents and surfaces for almost the entire year, with Grand Slams, Masters tournaments, team competitions and exhibition commitments leaving relatively little time for sustained recovery.

Players increasingly have to balance the pursuit of ranking points and prize money against the risk of entering major tournaments already carrying physical problems.

For Sinner, the decision to withdraw represents a particularly significant concession. As the world No. 1 and one of the two dominant players of his generation, he would have entered New York with a realistic opportunity to finish the season with another major title. Instead, his team has chosen the longer-term calculation: protecting a 24-year-old athlete whose career could still extend for another decade.

Draper faces a different but equally important challenge. His talent has already taken him to No. 4 in the world and within two victories of a Grand Slam title, but repeated injuries are beginning to shape his career as much as his results.

Their withdrawals leave the US Open without two of its most compelling players before the first ball has even been struck.

For Alcaraz, Zverev, Djokovic and the chasing group, the competitive landscape has suddenly opened. For Sinner and Draper, however, New York will instead become another reminder that in modern tennis, surviving the season can sometimes be as difficult as winning it.

The 2026 US Open begins August 23, but one of its biggest stories has already been written: the world’s leading player will not be there.