Rafanoy if you are around, like what I am reading from Darren Cahill on Jannik Sinner,
"Jannik is one of the most interesting talents in tennis and so I have followed his evolution.And in person he confirmed the idea I had formed.An extremely polite guy, hard worker and passionate about his work.Which makes everything easier"
I know for a fact Cahill will not put up with anyone that doesn't work hard, I remember he and Halep had had a parting of the ways once,Cahill didn't like her attitude, she cleaned up her act and they got back together.