Alcaraz used the occasion to not only celebrate the presence of the two Spaniards atop the rankings but also to dub Nadal as the "greatest of all time" — much to the delight of the Twitterati.
One user stated that even the "top players" know who the GOAT was, before suggesting that "spreadsheets and twitter cultists" be ignored.
"Even the actual top players know who the real GOAT is. Don't let spreadsheets and twitter cultists tell you otherwise," they wrote.
Echoing the sentiment, another fan described Nadal as "the best in history." The user went on to express pride in having two Spaniards at the top of the rankings.
"Proud of these two cracks, NADAL THE BEST IN HISTORY, at the moment for sure, if they were from another country there would be no doubt, how much envy there is," the user stated.
Others took a moment to compare the career trajectories of both Nadal Alacaraz, with one user stating that the former was a "legend" and the latter was on his way to becoming one.
Another fan, meanwhile, said that they were proud of Nadal's illustrious 22-year-long career before adding that Alcaraz had just begun his "great career."
"They deserve it!!!! They are two great powerhouses and two geniuses on the court!! Rafa legend and you are on your way to being one, congratulations to both of you for such a well-deserved achievement!!! Only you can do it, (translated)."
"For those who love tennis, even if they are not Spanish, it is a great satisfaction for you, for Spain, for your fans. Proud of my Rafa for 22 years. Carlos you are at the beginning of a great career, congratulations, (translated)."
Several fans celebrated the fact that the two Spaniards were atop the rankings ladder, with one user dubbing the moment "historical."
"HISTORICAL. Congratulations machines! You are the pride of all Spain," they wrote.
"A great pride for Spain, the confirmation in a great way to deliver the generational witness. Many congratulations to both of you (translated)," another tweet read.
"Happy for you both, Spain must be proud. Reminds me of Sampras and Agassi USA," they wrote.
Rafael Nadal, Carlos Alcaraz eye strong finishes to the 2022 season
Both Carlos Alcaraz and Rafael Nadal have taken home Grand Slam trophies this season — with the former winning his maiden Major at the US Open and the latter triumphing in Melbourne and Paris.
The duo's strong performances over the course of the season have seen them qualify for the season-ending ATP Finals.
Alcaraz is currently playing in Astana and will be eyeing a strong finish to his breakthrough season. Nadal, meanwhile, has taken some extra time off to recover heading into the final leg.