Federer on Sinner: "It's every athlete's nightmare".

Asked to comment on the Jannik Sinner affair, Roger Federer cast no doubt whatsoever on the Italian's guilt, although he acknowledged that the circumstances of the investigation raise questions.

Turning to the wider issue of doping controls and their impact on the life of a professional player, he explained: "It's the nightmare of every athlete and every team to have to deal with these kinds of accusations and problems.

We take these tests every day and fill out forms all day long.

Every morning, when you wake up, you wonder: 'Is someone going to come to my door to test me?'

It's really complicated."