Novak Djokovic's biggest obstacle to winning his 25th Grand Slam title is not Alcaraz or Sinner.

“I was stopped at the semifinals in three Grand Slams this year, losing to these guys who are incredibly strong and in great form,” Djokovic admitted earlier this month after his run at the US Open was ended by Alcaraz. The legendary player, who holds 24 Grand Slam titles, has been halted at the semifinals in all four majors this season, unable to advance further in his quest for that elusive 25th Grand Slam victory.

After withdrawing from the Australian Open at the start of the year due to a hamstring injury, Djokovic was eliminated by Sinner in both Paris and Wimbledon, and then by Alcaraz at the US Open. However, according to a well-known coach, the true reason behind the Serbian’s defeats may not be the rise of Sinner and Alcaraz.

Mouratoglou — the renowned coach who helped Serena Williams win 10 of her 23 Grand Slam titles — recently shared his thoughts on Djokovic’s “Grand Slam struggles.” He believes Djokovic may have come to realize that he is no longer invincible as he once was, a belief he firmly held before the emergence of Alcaraz and Sinner two years ago.

“It’s unbelievable that two years ago Novak was still at the pinnacle of tennis. In 2023, he was undoubtedly the strongest player: winning three Grand Slams and reaching the final of a fourth,” Mouratoglou said. “At that time, Novak said, ‘36 is the new 26, and my body is in perfect condition.’” He recalled this in a post on September 22. But now, “the narrative has changed. From being untouchable to losing to Sinner and Alcaraz. Now, he admits: ‘My body is no longer able to compete with these two in five-set Grand Slam matches.’”

Mouratoglou emphasized: “At Roland Garros, some limitations were already visible. By Wimbledon, it was undeniable. At the US Open against Alcaraz, he appeared exhausted after just two sets.” Simply put, his season’s trajectory went from “my body is perfect” to “my body is starting to hold me back due to age.” He further pinpointed the root cause of Djokovic’s Grand Slam failures: “The real issue is not whether his body has weakened, but that he seems to believe it has. And this shift in belief is new.”

In Mouratoglou’s view, the change in Djokovic’s mindset is “massive. Novak’s greatest strength has always been his unshakable confidence. If that inner belief fades, his physical condition will also decline.” He even hinted that Djokovic might never win his 25th Grand Slam, saying, “If Novak feels he can no longer win a Grand Slam, I don’t think he will continue playing for much longer.”

Djokovic’s only title in 2025 came at the Geneva Open, marking his 100th ATP Tour victory in his career. However, given his level, such a “title drought” this season is unusual. At 38 years old, the younger generation seems to have finally caught up to and surpassed him on the biggest stages, a fact Djokovic himself acknowledged in a candid self-assessment.

At this year’s US Open, Alcaraz did not allow Djokovic to win a single set. The same was true in the French Open and Wimbledon against Sinner. Although Djokovic reached the semifinals in all four Grand Slams in 2025, he revealed an unavoidable weakness. “I’m satisfied with my tennis level, but the problem lies in physical endurance,” he said during the US Open.

He went on to frankly evaluate his performances against the Spaniard and the Italian. Looking ahead, his tone was somber: “All I can do is try my best. Overcoming Sinner and Alcaraz in five-set Grand Slam matches will be extremely difficult for me. I think I still have a chance in three-set matches, but five sets are just too tough.”

After four consecutive Grand Slam semifinal losses, people naturally wonder if he has considered retirement. The truth? At least for now, he hasn’t. Djokovic still yearns for that coveted 25th Grand Slam title. “I will keep fighting, aiming to reach finals and compete for the title, at least giving it another shot.” But he also warned everyone: “It will be an incredibly tough challenge.” Do you think Djokovic still has the drive to chase another Grand Slam victory?(Source: Tennis Home, Author: Huohua)