Alexander Zverev lost his opening match at the Paris Masters shortly after ascending to the world number one ranking, becoming the fifth man in ATP history to suffer a first‑match defeat as the top‑ranked player.
According to a report, four other players have previously experienced the same fate, though their names were not detailed in the initial summary.
The German's early exit marks a rare occurrence in men's tennis, where the new world number one typically enjoys a strong start to his reign.
