When Jannik Sinner strides onto the terre battue of Court Philippe-Chatrier this week, he will carry more than a racket. He arrives in Paris nursing an extraordinary 29-match winning streak, holding five Masters 1000 titles already this season, and with the career grand slam tantalisingly within reach after conquering Melbourne, New York and Wimbledon. Yet the Italian’s coronation as the game’s pre-eminent force is unfolding against a backdrop of unusual labour unrest. On the eve of the tournament, Sinner and his peers deliberately truncated their media obligations, a choreographed protest over stagnant prize money and the lack of a meaningful pension scheme. “We are waiting more than a year for a small answer, and it’s not nice,” he said, casting himself, however reluctantly, as a unionist in tennis whites.

Viewed from Rome, where Sinner’s clay-court hegemony was recently extended at the Foro Italico, a familiar paradox is unfolding. He has dominated the dirt so thoroughly — winning at Indian Wells, Miami, Monte-Carlo, Madrid and Rome — that he himself acknowledged it is “better to feel tired because you are winning than to feel perfect and lose early”. That admission of fatigue, however, is freighted with risk. The last man to mount such a long surge before Paris, Novak Djokovic in 2011, was halted by Roger Federer in the semi-finals. Italian analysts note that Sinner’s camp must now calibrate his training load with surgical precision, balancing the euphoria of victory against the physical depletion that lurks behind his relentlessly metronomic baseline game.

The labour dispute simmering beneath the surface provides a new lens through which to view Sinner’s authority. He insists the boycott is “not against journalists” but about respect, and he explicitly linked it to the pension concerns of players who never reach the game’s summit. Such a stance, reported from Milan with a certain surprise, marks a departure for a champion still just 23 years old. It reveals a maturity that will be tested off the court as much as on it, as tournament directors in Paris and at the US Open come under pressure to redistribute the sport’s wealth more equitably. That Sinner, the embodiment of the meritocratic dream, has become a spokesman for the rank and file is a narrative twist that no one predicted even six months ago.

From a historical vantage point, the stakes this fortnight are immense. As Sydney observers point out, none of the fabled triumvirate of Federer, Nadal and Djokovic ever managed to hold all four major titles in the same calendar year, and Sinner’s only defeat this season — a seismic Australian Open semi-final loss to Djokovic himself — extinguished any hope of a calendar slam. But the career grand slam remains very much alive, and the absence of his great rival Carlos Alcaraz, still sidelined by injury, has cleared the draw of the man who denied Sinner in last year’s Roland Garros final, a wrenching five-set loss in which three match points slipped away. That trauma, Italian sources insist, has not faded; it has only sharpened his hunger.

Should Sinner lift the Coupe des Mousquetaires in a fortnight, he will become the first man since Rod Laver in 1969 to hold four consecutive major titles, a feat that would reorder the sport’s historical landscape. But the twin pressures of fatigue and the off-court activism swirling around the locker room inject a fragility into the narrative. The world No 1’s campaign is thus not merely a pursuit of sporting immortality, but a referendum on whether modern tennis can sustain a champion who dares to challenge the structures that sustain it.