Jannik Sinner will be looking for ways to change his fortunes against rival Carlos Alcaraz after the US Open final.

Sinner was beaten by Alcaraz in four sets, which was his second Grand Slam defeat to the Spaniard this year.

Not only was the Italian unable to defend his US Open title, but now Alcaraz has also dethroned Sinner as world number one.

Sinner continues to struggle in the head-to-head against Alcaraz, and he has now been told what he needs to change to improve this.

Carlos Alcaraz of Spain, finalist Jannik Sinner of Italy during the podium ceremony following the Men's Singles Final match on day fifteen of the 2025 US Open Tennis Championships at USTA Billie Jean King National Tennis Center.Photo by Jean Catuffe/Getty ImagesPatrick Mouratoglou names the four changes Jannik Sinner needs to make to challenge Carlos Alcaraz

Sinner’s serve has come under particular scrutiny after the US Open final, and he was particularly critical about his own game in his post-match press conference.

In this press conference, Sinner admitted that he was too ‘predictable’ and wanted to work on adding more variety to his game.

Naomi Osaka’s former coach Patrick Mouratoglou has now reacted to these comments, claiming that Sinner needs to implement these changes in all of his matches not just against Alcaraz.

Mouratoglou particularly highlighted using more serve and volley tactics, drop shots, as well as just more overall variety and pace.

“Even if he’s not unpredictable, he’s winning easily the immense majority of the matches throughout the year,” Mouratoglou said on Instagram. “Now, if he needs to be more unpredictable as he says, he’s prepared to lose matches sometimes.

“Why? Because what you work in practice, if you don’t do it during the matches, you’re not going to do it in a Grand Slam final, because you’re going to do what you’re used to be doing. So he knows that from now on, he’s going to serve and volley more, drop shot more, probably more variety in the game in general, change of pace, stuff like that.

“He will do it during the matches, because he needs this to become a habit, something automatic, and he’s prepared to pay the price for the progress he needs to do to beat Alcaraz in the future.”

When can Jannik Sinner and Carlos Alcaraz next play one another?

Four of Sinner’s five defeats in 2025 have come against Alcaraz, with tennis fans now counting down until their next encounter.

Sinner has a busy schedule planned for the rest of the year, but Alcaraz will not be at his next tournament in Beijing.

The next tournament they will both be at is the Shanghai Masters, where Sinner is the defending champion.

However, if they are to meet again then Alcaraz will have to do something he has never done before, having never surpassed the quarterfinals of the Shanghai Masters before.

Before then, Sinner will play at the China Open, which gets underway on Thursday, September 25.