Novak Djokovic regained the No. 1 ranking from Carlos Alcaraz yet again.

Djokovic made a triumphant return to the US Open for the first time since 2021 when he defeated Alexandre Muller in straight sets in his opening round matchup.

In the process, he also pipped Alcaraz to the top spot as all the Serbian superstar needed was a single win at Flushing Meadows in order to overtake his rival who only had a 20-point lead following their Cincinnati Open final.

It is the seventh time the pair have exchanged the No. 1 ranking in 2023 with Alcaraz having been at the summit since June 26. The Spaniard will still remain No. 1 for now as the ATP rankings will only update upon the US Open's conclusion next month.

However, when Djokovic does return to the No. 1 spot, he will extend his record for most weeks at the top spot to 390 — remarkably 80 weeks more than the previous record held by Roger Federer as well as 13 more than Steffi Graf's record of 377 on the WTA (via Tennis 365).

The only question now is how much of a lead Djokovic can generate over Alcaraz. With his opening round win, the 36-year-old now holds a 25-point lead.

Even if one assumes Alcaraz will defend his 2,000 points in New York, Djokovic could have a lead of 70 if he only makes it to the next round, 160 if he makes it to the last 16, 340 if he makes it to the quarterfinals, 700 if he makes it to the semifinals and 1,180 if he finishes runner up to Alcaraz.

If he were to defeat the reigning champion in the final, he would have as much as a 2,780-point lead which would all but guarantee another finish as the year-end No. 1. The lead could be even bigger if Alcaraz were to exit earlier.

That is why it's imperative for Alcaraz to win the US Open if he hopes to finish a second year in a row as the top-ranked player in tennis. The good news for the 20-year-old, however, is following the US Open, he doesn't have that many points to defend.

Additionally, he could even gain some points later on in Astana, Basel and Paris where he exited early last year. Djokovic, in comparison, is defending just over 5,000 points from the US Open onwards until February.

All that means is we could be in store for even more exchanges of the No. 1 ranking between Novak Djokovic and Carlos Alcaraz in the coming months.