ATP tennis’s biggest headliners are players not in action this week at the Mubadala Citi Open. They are Jannik Sinner, Stefanos Tsitsipas, and Alexander Zverev. At issue with all three players is the internal changes to their teams.
Jannik Sinner
By now you have probably heard that Jannik Sinner re-hired his fitness trainer, Umberto Ferrara. Ferrara is the person in question who purchased the first aid spray that had the banned substance used by Sinner’s former physio resulting in the failed doping tests and suspension.
Jannik Sinner has re-hired fitness trainer Umberto Ferrara.
Sinner previously parted with Ferrara for his part in the clostebol case: Ferrara purchased the spray, containing clostebol, which physio Giacomo Naldi then used on his own hand and inadvertently contaminated Sinner.
— James Gray (@jamesgraysport) July 23, 2025
People have shared their outrage at this decision including one of Sinner’s biggest critics, Nick Kyrgios. While I admit it was a bit of a surprise that he made this choice, I do not think it is anything seedy about it.
Unfortunately this isn’t @TennisCentel https://t.co/zawOhkz7KQ
— Nicholas Kyrgios (@NickKyrgios) July 23, 2025
Tennis players travel the world with their teams, and in many cases, they spend more time with this close circle than their family members. Sinner is World No. 1. He has won Grand Slams before and after the suspension, with and without Ferrara. Clearly, he feels most comfortable with Ferrara and knows that the world and authorities that be in tennis doping will be testing him vigorously.
Stefanos Tsitsipas
It is hard not to notice that Stefanos Tsitsipas‘s inner circle is crumbling around him. I am still saddened that he and girlfriend Paula Badosa reportedly broke up. The derogatory comments from his coach of the moment Goran Ivanisevic did not help. Probably the best news coming out of Tsitispas’s camp is that he and Ivanisevic are going their separate ways. It remains to be seen if it is good news that Tsitsipas is back working with his family members.
“I thought it was a joke”
Hall of famers shocked by Goran Ivanisevic’s critical comments towards Stefanos Tsitsipas 😳#Wimbledon pic.twitter.com/ER4kdC9c8s
— Tennis Channel (@TennisChannel) July 4, 2025
Alexander Zverev
Alexander Zverev recently raised eyebrows by working under the watchful eye of Toni Nadal at the Rafael Nadal Academy. Many speculated that Zverev was seeking new coaching after a disappointing 2025.
Some more videos of Alexander Zverev’s work with Toni Nadal
📸functionaltennis, antoninleborne Instagram pic.twitter.com/WTeu4Uw4cw
— ilyza1002 (@ilyza1002) July 16, 2025
Reports are surfacing that Toni Nadal will not be Zverev’s next head coach. Zverev has an open invitation to come to the Academy for training blocks whenever he feels it is necessary.
