Umberto Ferrara worked as Sinner’s fitness coach until last August, when he left the team five months after the world number one tested positive for clostebol. He left around the same time as Naldi, ...

Jannik Sinner has revealed why he rehired Umberto Ferrara after previously sacking the fitness trainer in the aftermath of.

Well, well, well. Look who just crashed the party and made himself right at home. While tennis fans were busy debating whether Jannik Sinner could maintain his world No.