In two weeks’ time, the best men’s tennis players in the world will descend on Melbourne for the Australian Open, the first Grand Slam tournament of the season and the first tennis milestone for 2025.

The ATP Tour is intriguingly poised, as the rest of the field try to prise the four Grand Slam trophies away from world No. 1 Jannik Sinner and world No. 3 Carlos Alcaraz, who split them two apiece in 2024. Novak Djokovic is in search of his record-breaking 25th major singles title with Andy Murray in tow as coach; world No. 2 Alexander Zverev and the rest of his generation are reckoning with how Sinner and Alcaraz have reconfigured the sport. An exciting crop of younger players are impatient to usurp their forebears, the American men are looking to take the next step and if the ATP Next Gen Finals is anything to go by, an 18-year-old from Rio de Janeiro called Joao Fonseca is going to be a problem very soon.

But all this could hinge not on games, sets and matches, but on the court in Switzerland that will decide the outcome of Sinner’s doping case. The Athletic’s tennis writers, Matthew Futterman and Charlie Eccleshare, outline the biggest men’s tennis storylines for the 2025 season.