All ATP Rankings Reconstructed
Week by Week

The ATP ranking was officially introduced on 23 August 1973, marking a major turning point in men's professional tennis. Prior to its introduction, tournament seedings were often determined subjectively, based on the opinions of journalists, officials, or tournament organizers.

Early publication frequency

Unlike today, the ATP ranking was not published on a weekly basis from the start:

• 1973–1977: rankings were released irregularly, often only a few times per year, typically around major tournaments or key moments of the season.
• 1978–1981: rankings became more frequent but were still not weekly, with updates sometimes occurring every two or three weeks.
• From 1982 onward: the ATP introduced a regular weekly ranking, establishing the continuous and standardized system used today.

This approach inevitably leads to ranking recalculations. The most significant result of this reconstruction is that Guillermo Vilas emerges as World No. 1 from 17 November 1975 to 16 January 1976.

In a comparable case, the WTA officially recognized Evonne Goolagong as World No. 1 retroactively in 2007, acknowledging historical inconsistencies in early ranking systems. We hope that, sooner or later, the ATP may take a similar step.

For this reason, building on research and historical reconstructions available online, we decided to reconstruct the ATP ranking on a week-by-week basis starting from the very first official ranking.