The two best men's players in the world are reconfiguring the sport before their opponents' eyes. They don't know what to do about it

Carlos Alcaraz was in fine form as he cruised to a first-round win at the Australian Open, but it was his comments on Jannik Sinner which drew attention.

When Carlos Alcaraz is on court for a training session, perhaps working on his newly revamped service motion, he’s doing so to buttress a game already good enough to claim four Grand Slam titles