Jannik Sinner has closed the gap to Carlos Alcaraz after winning the Vienna Open title on Sunday.
The Italian overcame cramps to win his fourth ATP Tour title of the season, defeating world number three Alexander Zverev 3-6, 6-4, 7-5 in the final.
As a result, Sinner gained 500 ATP points and is now 840 points behind Carlos Alcaraz, who did not compete at the Vienna Open or the Swiss Indoors event.
Sinner surrendered the world number one spot after losing the US Open final to Alcaraz, although he still has the opportunity to reclaim the position before the conclusion of 2025.
After winning the Six Kings Slam earlier this month, Sinner suggested to Netflix that it would be impossible to catch Alcaraz in the rankings before the end of 2025.
However, the prospect of Sinner ending the year as world number one remains a possibility.
How Sinner can catch Alcaraz before the end of 2025
After winning the Vienna Open, Sinner is on 10,500 ATP points. Alcaraz is on 11,340 – 840 points ahead of Sinner.
Sinner has no points to defend at the Paris Masters, as he did not compete at the tournament in 2024.
Alcaraz, meanwhile, will defend 100 points at the tournament after losing to Ugo Humbert in the 2024 Paris Masters round of 16.
| Player | ATP Ranking | Points |
| Carlos Alcaraz | 1 | 11,340 |
| Jannik Sinner | 2 | 10,500 |
| Alexander Zverev | 3 | 6,160 |
| Taylor Fritz | 4 | 4,685 |
| Novak Djokovic | 5 | 4,580 |
Therefore, if Sinner wins the Paris Masters, Alcaraz will need to reach at least the semi-final stage to maintain the number one spot.
Sinner would gain 1000 points if he wins the title. If Alcaraz reaches the semi-finals, he will gain 300 points [400 points minus the 100 from the 2024 Paris Masters].
In this scenario, if Alcaraz reaches the quarter-finals, he will gain just 100 ATP points and lose the number one ranking to Sinner.
If this were to happen, Alcaraz would likely immediately reclaim the number one spot when Sinner’s 2024 ATP Finals points are removed on November 10.
Sinner won every match during the 2024 ATP Finals, meaning he has 1,500 points to defend in Turin this year. Alcaraz has only 200 points to defend after exiting at the round robin stage in 2024.
If Sinner repeats in Turin, and/or Alcaraz exits the tournament early, the Italian could then reclaim the world number one spot.
The last 10 year-end world number ones
Only five players have finished an ATP Tour season as the year-end world number one in the past decade.
Novak Djokovic has dominated the statistic, having claimed year-end world number one status on five occasions since 2015.
Rafael Nadal achieved the feat twice in the same time span, in 2017 and 2019.
| Year | Player |
| 2015 | Novak Djokovic |
| 2016 | Andy Murray |
| 2017 | Rafael Nadal |
| 2018 | Novak Djokovic |
| 2019 | Rafael Nadal |
| 2020 | Novak Djokovic |
| 2021 | Novak Djokovic |
| 2022 | Carlos Alcaraz |
| 2023 | Novak Djokovic |
| 2024 | Jannik Sinner |
Jannik Sinner, Carlos Alcaraz and Andy Murray have achieved the feat once, in 2024, 2022 and 2016 respectively.
