Jannik Sinner leads the ATP rankings point table comfortably at the moment after his Wimbledon triumph. Sinner has 12030 points now, while Carlos Alcaraz, the Wimbledon runner-up, has 8600 points. Novak Djokovic is currently ranked sixth with 4130 points.
At this point in time, Jannik Sinner is the runaway winner as far as the ATP rankings are concerned. However, the equation could change if Alcaraz manages to perform well in the North American hard court swing.
Carlos Alcaraz has very few points to defend in the next few big tournaments:
Alcaraz did not play at the National Bank Open in Toronto last year, which means that he will not have any points to defend in the tournament. He can, however, gain 1000 points by winning the event.
Similarly, he will have only 10 points to defend at the Western & Southern Open in Cincinnati, as he lost in the round of 32 in that tournament last year. The 22-year-old Spaniard lost in the second round of the US Open last year, giving him only 50 points to defend this year. Thus, Alcaraz has only 60 points to defend in total in the North American hard court swing and has 3940 (2000+1000+1000-60) points to gain effectively.
Jannik Sinner has a lot of points to defend:

In comparison, Sinner has a lot of points to defend in the next few tournaments. As the defending champion at the US Open, he will have 2000 points to defend. Moreover, he won the title in Cincinnati in 2024 as well. Hence, he will have 1000 points to defend there this year.
The 23-year-old Italian lost in the quarterfinals of the National Bank Open in Toronto last year, which gives him 200 points to defend there this year. Thus, Jannik Sinner has 3200 points to defend in all in the next three tournaments. If the Italian falters early in each of those tournaments, Alcaraz will have a great chance to replace him at the top by doing well in them.
Novak Djokovic might not play in all three tournaments this year either:
Novak Djokovic, meanwhile, did not play in either Toronto or Cincinnati last year. Hence, he will not have any point to defend in those tournaments. However, the 38-year-old Serb does not play in too many tournaments aside from Grand Slams these days, and hence, might not play in those two Masters 1000 tournaments this year either.
Djokovic lost in the third round at the US Open in 2024, giving him 100 points to defend this year. That means that the Serb can gain 1900 (2000-100) points by winning the US Open this year, even if he does not play in either Toronto or Cincinnati.
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