Carlos Alcaraz broke into the ATP top 5 rankings on Monday, at the age of just 19 years, two months and 20 days. Alcaraz is the second-youngest male player to reach that milestone in the 21st century, only behind fellow countryman Rafael Nadal.
Nadal entered the top five when he was 18 years, 11 months and six days old. Apart from the two, Novak Djokovic is the only player this century to have cracked the the top five as a teenager.
Speaking on the ATP Tour, an ecstatic Alcaraz stated that he would continue to work hard to reach the top spot.
"It means a lot," he said. "The hard work that I put in every day for reaching my dreams, No. 1, and little by little I’m reaching my dream. Top five for me is pretty amazing, and I will keep going to be No. 1."
But some Djokovic fans are not happy with the development, as the Serb is down to seventh in the rankings despite winning the Wimbledon title earlier this month.
One fan took a dig at the ranking system while also praising the Spanish youngster.
"As I mentioned in one of my previous tweets, it is well deserved but the whole ranking lost a bit of sense having the best player out there prevented from defending/earning 10k points this year (AO, USA). It's easier now to be in the top 5 than it should be," a fan wrote.
Another fan alluded to Djokovic being treated unfairly, in contrast to Roger Federer staying in the top 10 without playing a game for two years.
"How is this rational, logical or even practical without exposing the systems used to hurt Djokovic? And Federer was in the top ten without playing a game for over 2 years," another user posted.
Another user called the entire ATP ranking system a "joke."
"This year's joke of the ATP ranking not awarding points for Wimbledon will put Djokovic below him," the fan posted.
Here are a few more reactions:
Carlos Alcaraz looking to defend his title in Umag this week

Carlos Alcaraz's maiden ATP singles title came at the Croatian Open last year. He now returns to Umang to defend his title, with the ATP 250 event set to be held from July 25-31.
The Spaniard has a challenge on his hands, with the likes of Jannik Sinner, Holger Rune, Sebastian Baez and Francisco Cerundolo also in contention. Last year, the 19-year-old defeated Lucas Pouille, Andrej Martin, Filip Krajinovic, Albert Ramos-Vinolas and Richard Gasquet to clinch the title.
He enters the tournament on the back of a 6-4, 6-7(6), 6-4 defeat to Italy's Lorenzo Musetti in the European Open final in Hamburg.
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