Sinner's reign at risk? The unexpected challenger who could take the No. 1 Spot

Neither Carlos Alcaraz nor Novak Djokovic can dethrone World No. 1 Jannik Sinner as he heads into the US Open as the top seed, following Alcaraz’s early exit at the Cincinnati Open and Djokovic’s decision to take a break before the final Grand Slam of the year.

While Sinner has reached the Cincinnati Open quarter-finals, he has capitalised on the loss of points by his main rivals, further extending his lead over them. The Italian currently holds a 1,500-point lead over Djokovic and a 1,600-point lead over Alcaraz. However, there remains one player who could potentially overtake him by the end of the US Open.

At the US Open, Sinner will defend 180 points after reaching the fourth round in 2023. However, his main contenders have significantly more points to defend: Alcaraz reached the semi-finals (780 points), and Djokovic was the champion (2,000 points).

If Sinner only reaches the quarter-finals in Cincinnati this week, he would lead the rankings with 8,960 points, followed by Djokovic with 7,460 and Alcaraz with 7,360. However, even if Djokovic wins the US Open, he wouldn’t gain any points and would remain at 7,460. On the other hand, if the Spaniard wins, he could only reach 8,640 points, which wouldn’t be enough to surpass Sinner, who is guaranteed to finish with 8,780 points after Flushing Meadows.

The only player who still has a chance to surpass Sinner in the rankings is Alexander Zverev (World No. 4). With 6,835 points so far, he remains in the competition at the Cincinnati Open. Should he win the Masters 1000 title, he would overtake both Djokovic and Alcaraz, returning to his career-high ranking as World No. 2.

This scenario would also have implications for the US Open. While Sinner would be the top seed, Zverev could secure a place on the opposite side of the draw, avoiding Sinner until a potential final. However, this also means that Alcaraz or Djokovic would be potential semi-final opponents for both the Italian and the German.

If Zverev wins the Cincinnati Open title, he would reach 7,635 points (and secure 7,275 points by the end of the US Open). If he goes on to win the title at Flushing Meadows, he could take the World No. 1 spot, although he would need Sinner to fall before the quarter-finals.