Hunch. Jannik Sinner, who beat Alexander Zverev in Turin in 2025, will miss this year's event with a knee injury, Al Jazeera reported on 12 October.
The final market resolves on the same Nitto ATP Finals site: YES if Zverev plays in the singles final on 22 November 2026, and NO if he goes out in the group or the semi-final, or withdraws before the final. If that page is silent, the tournament's results archive, BBC Sport and The Guardian settle it.
We looked for cases where a tennis player ended a season as world number one for the first time, after winning two or more Grand Slam titles that year. We found ten such events since 1991, four for men and six for women. The number one won three of them.