He has become familiar with setting landmarks.
When he won his maiden Slam title at the US Open last year he become the youngest champion of a men's major since storied compatriot Rafael Nadal at the 2005 French Open.
He also became the youngest man to ascend to the world number one ranking.
The modest, muscular star from the small Murcian town of El Palmar in Spain's south-east hit the giant-killing jackpot at Madrid in 2022 when he became the only man to defeat both Nadal and Djokovic at the same clay-court event.
For good measure, he achieved it on back-to-back days on his way to the title.
"Carlos' intensity and speed is something you rarely see," said Rafael Nadal's uncle and former coach Toni Nadal.
'Never gives up'
"His game follows the same path as Rafa; he never gives up until the last ball and has that characteristic intensity."
Nadal was also 19 when he won the first of his 22 Grand Slam titles at Roland Garros in 2005.
However, Nadal has always pleaded with fans not to put pressure on Alcaraz by making bold comparisons.
"I forgot what I was like at 19," said Nadal. "The only thing we can do is enjoy the career of an extraordinary player like Carlos.
"If he manages to win 25 Grand Slams, it will be fantastic for him and for our country. But let him enjoy his career."
Despite Nadal's reluctance, making comparisons is unavoidable.
Nadal won the first of his 92 titles at Sopot at the age of 18 in 2004.
Alcaraz, who learned the game at a tennis school run by his father, was also 18 when he captured his maiden ATP trophy at Umag in 2021.
Both men are fiercely protective of their private lives, enjoy passionate crowd support and build their games on steely defence and thrilling, flamboyant attack.
Nadal famously fought out a five-hour and 53-minute Australian Open final in 2012, only to lose to Djokovic.
Four years earlier, he won his first Wimbledon crown in a four-hour 48-minute epic against Roger Federer in a match widely hailed as the greatest Slam final of all time.
'Competitive kid'
"I know that I am a very competitive kid. I compete whenever I play anything - golf, petanca," said Alcaraz. "I don't like to lose."
At his side is coach Juan Carlos Ferrero, the 2003 French Open winner who also took the number one ranking at the US Open later that year.
"I would love for Carlos to win 30 Grand Slams. There will be a lot of chances," said Ferrero, who began working with Alcaraz when he was just 15.
Alcaraz was already winning junior European and Spanish titles in lower categories under the guidance of Albert Molina, an agent with IMG.
Molina established the Alcaraz-Ferrero partnership.
Ferrero then brought Alcaraz into his academy in Valencia, 120km from El Palmar.
His raw potential soon attracted sponsors, with marquee brands such as Nike and Rolex rushing to sign up Nadal's heir apparent.
The tennis team around the prodigy was also expanding and soon included a physical trainer, a physiotherapist and the support of psychologists and doctors.
An indication of his potential was obvious at the Rio clay court event in 2020 when he was just 16, and ranked 406 in the world, he shocked Albert Ramos Vinolas to register his first ATP win.
Alcaraz and Ferrero have developed a deep professional and personal bond.
That relationship was sealed when Ferrero, having returned home following the death of his father, quickly crossed the Atlantic again just in time to see Alcaraz win his first Masters title at Miami in March last year.
"Let him flow, let him play," said Ferrero when asked to plot his pupil's future trajectory.
For Alcaraz, the sky is the limit after he dethroned Djokovic to confirm his emergence as the sport's new king.
