**Alexander Zverev’s dominant 2026 campaign, capped by French Open and US Open titles plus consistent indoor hard-court results, underpins the 79.5% implied probability that the Nitto ATP Finals champion finishes unbeaten.** With Jannik Sinner sidelined for the remainder of the season by injury, the field lacks its recent dominant force, elevating Zverev and Carlos Alcaraz as the clearest threats in Turin’s round-robin format. Zverev’s serve-heavy game and prior ATP Finals experience align well with the indoor surface and shorter best-of-three sets, while recent form from Shanghai and the fall swing shows few signs of vulnerability among top qualifiers. The competitive depth among emerging players like Ben Shelton and Daniil Medvedev creates upset potential but has not shifted trader consensus away from a likely straight-sets run by the leader.