WIMBLEDON, England — The vision of Jannik Sinner covered in sweat and red dust, bleary-eyed and emotionless, will not soon be forgotten by those who watched last month’s epic French Open final matching the current standard-bearers in men’s tennis. Sinner led by two sets and had three championship points against Carlos Alcaraz but lost the trophy anyway. After 5 hours 29 minutes, there was nothing he could do but stare into the void.