"Sinner needs rest and should not return to play until he feels 100% physically," Macci wrote on social media on 23/9. "He has a long journey ahead, but he must listen to his body, or he risks becoming a cautionary tale."

"Cautionary tale" is Macci's analogy for the danger of Sinner quickly falling behind if he pushes himself to play before fully recovering. The Italian player is slated to return at the China Open, which starts in Beijing on 30/9, following a two-month absence.

Sinner has not competed since winning Wimbledon in July. A knee injury led him to withdraw from the Canada Open, Cincinnati Open, and US Open, causing him to miss the entire North American hard-court season.

Sinner reacts after losing a point in the Wimbledon men's singles final against Alexander Zverev at the All England Club, London, England, 12/7/2026. Photo: Reuters

Before his injury, the world number one's physical condition also raised concerns at Roland Garros. Sinner showed signs of exhaustion in hot conditions, losing to Juan Manuel Cerundolo in the second round. This sparked questions about his endurance given the demanding and increasingly dense tournament schedule.

Macci believes Sinner and his team possess enough experience to determine the appropriate time for his return. However, the 71-year-old coach emphasized that the desire to compete should not override the warning signals from the body.

"Jannik and his team understand the path ahead, as well as when he should return," Macci said. "He is a formidable opponent, very hard to shake, and always wants to compete with everyone. Look at what he has achieved this year: playing fearlessly and reaching a new level."

Before his season was interrupted by injury, Sinner displayed outstanding form with 44 wins in 47 matches and six titles. He completed the "Sunshine Double" at Indian Wells and Miami, won the Monte Carlo Masters, and then conquered Wimbledon. This series of achievements solidified the Italian player's world number one position, but also reflected the significant workload his body endured in the first half of the year.

Macci coached Serena and Venus Williams early in their careers, later working with Andy Roddick, Jennifer Capriati, and Maria Sharapova. He is known for discovering and training many young talents before they reached their peak.

Macci's warning comes as Sinner races against time to be fit for the China Open. The ATP 500 tournament in Beijing marks the start of an important late-season stretch, preceding the Shanghai Masters, Paris Masters, and ATP Finals.

Sinner has resumed training but has not definitively confirmed his participation in Beijing. His knee's mobility and load capacity will be closely monitored, as the Italian player must also consider his goal of defending his world number one ranking by year-end.

Vy Anh