Former coach calls Jannik Sinner the 'Chosen One' but slams Carlos Alcaraz's serve

Tennis is in good hands. I should probably start there as it becomes important in just a bit. But both the ATP and WTA have a lot of good and very young players who are going to make the sport important for the next decade-plus. On the men's side, Jannik Sinner and Carlos Alcaraz are both 22 years older or younger., for instance, and will likely battle for Grand Slams for years to come.

Sinner appears to be the ascending player currently. Alcaraz has not won a title since being victorious at Wimbledon last July. Sinner has won four tournaments since then and that includes winning his first Grand Slam after he defeated Daniil Medvedev in the Australian Open final.

Neither player has any real fatal flaws. Both move around the court extraordinarily well and can hit balls with pace from anywhere to anywhere on the court. They both have very good touch as well, though Alcaraz's is otherworldly and may be among the best tennis has ever seen.

Jannik Sinner versus Carlos Alcaraz will be tennis' next great rivalry

But former Serena Williams coach Rick Macci has strong thoughts on both Carlos Alcaraz and Jannik Sinner. Of note is that Macci can be observationally critical of players, but with great knowledge of the game and normally with a positive bent. But Macci sees a real problem with Alcaraz's serve.

On X (the artist formerly known as Twitter) this week, Macci posted, "Biomechanically (Alcaraz) checks most boxes. But the racquet leaks 25 percent too soon into the back. Shoulder set up is microscopically off creating less natural fluidity and not delivering the optimal head speed."

Is Alcaraz's serve fixable? Of course, and Macci knows that. But while 25 percent does not sound like that much, that number is actually very high in a sport with extremely small differences can be the reason a player wins 10 Grand Slams or two. If Alcaraz is not hitting his serve as well as he hopes that could be the reason Sinner ends up being the bigger winner of the two players long-term.

That is part of the key. Sinner and Alcaraz are going to be battling for tennis supremacy for at least a decade, barring injury or a lack of motivation. This is great for tennis fans, though. We are witnessing the end of careers such as Rafael Nadal and Novak Djokovic, but we are seeing the blooming of Sinner and Alcaraz. That is a good thing.

As far as Sinner, Macci called in the "Chosen One" in a separate post. Calling Sinner that might be a tad too early. Macci wrote, "...now he is the Chosen One but the number one quality I see inside and out of Italian flame thrower is number one." But Macci knows more than I do so he is likely correct.

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