Carlos Alcaraz is just one win away from finishing the year as World No. 1, but the battle at the ATP Finals is far from over. Even after his big comeback win against Taylor Fritz in 7‑5, 6‑3, the Spanish star knows there’s one key factor that could give his rival, Jannik Sinner, a real advantage – something he’s fully aware of and determined not to let happen.

Against Fritz, he lost the first set 6‑7 (2) but fought back to win 7‑5, 6‑3 in almost three hours. Now, he only needs to beat Lorenzo Musetti in his last round-robin match or win in the semifinals to secure the top spot for the second time. When asked about being so close to No. 1, Alcaraz said, “I try not to think about it, to be honest. Obviously, it’s going to be a really big match for me. I will try not to let the nerves play a bad time for me in that match.” In other words, he’s focused on staying calm and not letting the pressure get to him.

If he did let nerves creep in, Sinner could seize the opportunity because he thrives under pressure. He rarely lets a bad point or the crowd affect his game, and his form indoors has been impeccable. As Sinner once said, “I like to dance in the pressure storm.” That’s the challenge Carlos Alcaraz faces: if he lets nerves or his indoor court troubles creep in, Sinner could use it to keep the race for year-end No. 1 alive.

Carlos Alcaraz added, “I’ll try to control the emotions, to control myself. I’ll think about my goals in the match. I’ll try to feel much better than today with my shots, with the serve, with everything.”

He also said, “Obviously, it’s going to be a big day. Right now, I’m going to enjoy this win and try to rest as much as I can to be ready for the match.” His approach is clear: stay composed, focus on preparation, and don’t let the pressure decide the outcome.

Carlos Alcaraz, now 2‑0 at the ATP Finals, could clinch a semifinal spot if Alex de Minaur beats Musetti later. But to seal his year-end ranking, he needs to beat Musetti in his next match. If not, he needs to reach the final. But at this point, Sinner needs to hope Alcaraz doesn’t reach the final while he sweeps the whole tournament undefeated to finish No. 1. It’s a tall ask, and Alcaraz doesn’t appear ready to make it happen.

Earlier today, Carlos Alcaraz produced 47 winners to Fritz’s 38 and managed to come back from a set down despite 14 aces from his American opponent. He now tops the Jimmy Connors group ahead of Fritz, who stands at 1‑1, while Alex de Minaur and Lorenzo Musetti are both 0‑1.

And as we know, only the top two finishers in each group advance to the semifinals. Sinner leads his group after beating Felix Auger-Aliassime in his opener on Monday. But nerves aren’t the only challenge Alcaraz faces. Could another problem, visible in today’s game against Fritz, give Sinner a chance for year-end No. 1?

Carlos Alcaraz faces another potential weakness

After his tough win over Taylor Fritz, Carlos Alcaraz admitted the match was challenging. “Well, it was pretty tight, the match. I think I was running more than him; I was struggling more than him,” he said. “In the first set, I didn’t serve well, and I think he was playing really, really comfortable from the baseline, with everything.”

Alcaraz’s words highlight one of the main weaknesses in his otherwise excellent game: his serve. Admittedly, his first serve is now in better shape, and with increased aggression, recent numbers show that he is hitting the ball better. For example, his first serve percentage, which languished at 53% during the Wimbledon final, had rocketed up to 83% by the US Open Final. Though it went down to 63% against Fritz’s 75%, Alcaraz had the better win percentage on his first serve (74% vs. 71%).

Despite the improvements he’s been making since last offseason, Carlos Alcaraz’s serve is not yet among the elite on tour. In 2025, he ranks 28th for first-serve points won (74%) and 25th for first-serve percentage landed (64%).

His second serve remains a potential weakness, often more defensive than offensive, and double faults have increased slightly (~1.8%) this year (2.8 vs. 2.1). Against Sinner, any lapse in Alcaraz’s serve could be costly, as was demonstrated in Wimbledon.

The takeaway is evident: Alcaraz needs to be at the top of his game to take on Sinner on a surface where he’s currently riding a 27-game win streak. The World No. 1 ranking is his to lose, but he will need to really fight for his maiden ATP Finals title.