Serena Williams’ ex-coach fires Jakub Mensik warning to Jannik Sinner, Carlos Alcaraz

Serena Williams’ childhood coach Rick Macci described Jakub Mensik’s game as “very special” and also warned Jannik Sinner and Carlos Alcaraz to watch out for the 19-year-old. 

After struggling with his game and form in early 2025, Novak Djokovic appeared to be destined to win the Miami Masters and finally win his 100th title. But what was expected to be the Serb’s big day, turned into the Czech’s big day after the rising star claimed a 7-6 (4) 7-6 (4) win in the Miami final to land his maiden Masters title.

Mensik, who has a great serve and a big game, went toe-to-toe with Djokovic throughout the match. And when the time came for the first and second sets to be resolved in tie-breaks, he also didn’t fail to deliver. With that kind of a performance, he didn’t leave room to anybody to argue that he just got lucky or anything like that.

“He already has a very special complete game and his serve is already hitting spots at the key moments with 130 mph juice. Everybody can pop it. But can you deliver the mail on time at the right time? The Czech checks that SERVICE BOX for sure. Top ten on the horizon,” Macci wrote of Mensik on X.

Macci’s warning to Sinner and Alcaraz: Mensik is coming for the top-5

By winning Miami and collecting 1,000 ranking points, the Czech also went from world No. 54 to ranked at No. 24 on this Monday’s updated ATP rankings list. And Williams’ childhood coach believes this is just the start. 

“Huge upside with huge serve. The leg drive innates the racquet at the right time and the angle of decent of serve is coming in with mustard from a launched and elevated 6 ft 4 frame to a spot. Jacob will be CZECKING Carlos and Jannik and the top 5 sooner than later,” Macci wrote in another X post. 

​Tennis World USA


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