Knee injury knocks former US Open champion out of Miami Open.
A familiar face has inspired Karen Khachanov's surge.
The Canadian is already benefitting from the presence of the Magician in his box.
The former Roland Garros Girls Singles champion is ready to make a big splash in Miami.
Two essential elements are key to 37-year-old Roger Federer's longevity.
Roger Federer has been both teammate and advisor for Belinda Bencic.
Upset in singles, world No. 1 aims to win doubles crown with partner Fabio Fognini.
