[jsackmann]

Shot-by-shot stats for almost 6,000 pro matches, including over 300 of Nadal's and 400 of Federer's: http://www.tennisabstract.com/charting/meta.html

Raw data for a large subset of those matches: https://github.com/JeffSackmann/tennis_MatchChartingProject

[necovek]

Wow, great source, thanks.