Returning as the defending champion, Jannik Sinner will be confident of picking up his second US Open title in 2025.

After struggling with an illness in Cincinnati, Sinner looks to be on the mend, which is good news for the Italian, given the US Open begins tomorrow.

Entering the tournament as the number-one seed, few would risk betting against Sinner in New York, although that’s not to say he won’t be challenged.

Jannik Sinner hits a forehand in a 2025 US Open practice sessionPhoto by Sarah Stier/Getty Images

Many expect Sinner to meet his greatest rival, Carlos Alcaraz, in the final, with the pair level at 1-1 in their two Grand Slam finals against one another this year, with the Spaniard winning in Paris and the Italian in London.

However, an ATP Tour legend has now named three ‘dangerous’ players Sinner could face before he even reaches the quarterfinals.

Paolo Bertolucci names three ‘dangerous’ players in Jannik Sinner’s draw

Writing for La Gazzetta dello Sport, 1976 Davis Cup winner Paolo Bertolucci suggested Sinner may have some issues in round two of the US Open.

“In the second round, Jannik [Sinner] faces [Alexei] Popyrin, and he needs to be in good form because the Australian knows the surface well and could be dangerous for Sinner,” he said.

To make that match happen, Sinner will need to beat Czechia’s Vit Kopriva, and Popyrin will need to beat Emil Ruusuvuori in the first round.

Jannik Sinner reacts during a practice session ahead of the 2025 US OpenPhoto by Sarah Stier/Getty Images

Bertolucci believes Sinner may have even more trouble in the fourth round, potentially facing two seeded players.

[Tommy] Paul or [Alexander] Bublik could be a threat in the round of 16 for Sinner,” he said.

“Especially considering the precedent in Halle, with Jannik’s unpredictable loss to the Kazakh. They are unpredictable players, both technically and tactically.”

At the 2025 Halle Open, Sinner was stunned by Bublik, losing to the Kazakh star in three sets 6-3, 3-6, 4-6.

Bertolucci thinks his fellow Italian will have an easier time of things should they play in New York, however, thanks to the best-of-five set format.

“[They are] only fearsome when playing two out of three sets: in three out of five sets, the top two in the rankings [Jannik Sinner and Carlos Alcaraz] always have the long run to recover from a slow start,” he said.

The 74-year-old then mentioned another big-name, who Sinner may have to take down en route to the title.

“Further down the line, Sinner could face [Alexander] Zverev in the semifinals,” said Bertolucci.

It’s clear to see that Sinner will have his work cut out for him if he wants to defend the title, but how well has he performed against the three ‘dangerous’ players Bertolucci named in his career so far?

Jannik Sinner’s record against Alexei Popyrin, Tommy Paul and Alexander Bublik

In total, Sinner has played 12 matches against Popyrin, Paul, and Bublik, leading the combined head-to-head 8-4.

Match Winner Loser Score 2025 Halle Open – R16 Alexander Bublik Jannik Sinner 3-6, 6-3, 6-4 2025 French Open – QF Jannik Sinner Alexander Bublik 6-1, 7-5, 6-0 2025 Italian Open – SF Jannik Sinner Tommy Paul 1-6, 6-0, 6-3 2024 US Open – R16 Jannik Sinner Tommy Paul 7-6, 7-6, 6-1 2023 Canadian Open – SF Jannik Sinner Tommy Paul 6-4, 6-4 2023 Halle Open – QF Alexander Bublik Jannik Sinner 7-5, 2-0 (RET) 2023 s-Hertogenbosch – R16 Jannik Sinner Alexander Bublik 6-4, 6-2 2022 Eastbourne – R16 Tommy Paul Tommy Paul 6-3, 3-6, 6-3 2022 Madrid Open – R64 Jannik Sinner Tommy Paul 6-7, 7-6, 6-3 2021 Madrid Open – R32 Alexei Popyrin Jannik Sinner 7-6, 6-2 2021 Miami Open – QF Jannik Sinner Alexander Bublik 7-6, 6-4 2021 Dubai – R32 Jannik Sinner Alexander Bublik 2-6, 7-6, 6-4

Jannik Sinner’s head-to-head record against Alexei Popyrin, Tommy Paul, and Alexander Bublik

Sinner is leading the head-to-heads against Bublik and Paul, but lost his sole career meeting with Popyrin.

Coming up short in the early rounds of the Madrid Open four years ago, Sinner fell in three sets to the Australian.

Alexei Popyrin celebrates his win over Jannik Sinner at the 2021 Madrid OpenPhoto by Gonzalo Arroyo Moreno/Getty Images

It’s not outrageous to say a lot has changed since then, however, and on the hard courts at Flushing Meadows, Sinner would certainly be expected to level the head-to-head at 1-1.

Popyrin shouldn’t be taken lightly, though, as he did stun Novak Djokovic at the US Open just 12 months ago.

Only time will tell who will emerge victorious should they face off at the US Open in 2025, but you certainly won’t want to miss any of the action when the tournament begins on Sunday, August 24.