Jannik Sinner shakes up staff after positive doping tests - ESPN

World No. 1 Jannik Sinner confirmed he had parted ways with fitness coach Umberto Ferrara and physiotherapist Giacomo Naldi after the two were deemed responsible for Sinner's two positive tests for a banned substance in March.

Speaking to reporters for the first time since the doping results and subsequent ruling by the International Tennis Integrity Agency (ITIA) were released Tuesday, Sinner praised Ferrara and Naldi for their work over the past two seasons in a news conference at the US Open but said he needed to make a change.

«Now, because of these mistakes, I'm not feeling that confident to continue with them,» Sinner said. «The only thing I just need right now, just some clean air. You know, I was struggling a lot in the last months. Now I was waiting for the result, and now I just need some clean air.»

On Tuesday, a day after Sinner won the Cincinnati Open, the ITIA announced Sinner had tested positive for low levels of clostebol, a banned anabolic steroid that can be used for ophthalmological and dermatological use, on both March 10 and March 18. He was provisionally suspended at the time but was able to compete while he appealed the findings.

According to the ITIA, an independent panel held a hearing on Aug. 15 and «determined a finding of No Fault or Negligence applied in the case, resulting in no period of ineligibility.» The ITIA added that the traces of the substance were a «result of contamination from a support team member, who had been applying an over-the-counter spray containing clostebol to their own skin to treat a small wound.»

Per the ruling, Ferrara purchased the spray and Naldi used it on himself prior to giving Sinner a massage, thus inadvertently contaminating Sinner.

Sinner was stripped of his