The American is aiming for his second win over the World No.1 in as many weeks.
Ongoing injuries prevent Juan Martin del Potro from returning to New York this year.
The Greek interrupted the match to address a buzzing fan in Cincinnati.
The 2014 champion will miss his favorite major.
One of tennis' fastest players shows a rare hands-on skill.
The Frenchman says being an elite, showstopping athlete is not all about natural talent.
The 38-year-old is a two-time US Open quarterfinalist.
