“I thought I was just going to just keep going,” he said. “It doesn’t work like that. Same work you did to get up there, the same work you need to keep going, keep working harder.”

Despite the cautionary tales, it is nearly impossible not to be swept up in the excitement of watching new talent burst onto the scene at one of the biggest showcases in sports. It is a breathless experience that tennis has long thrived on.

Alcaraz, a Spaniard already burdened by a nickname, the Next Rafa, a reference to his countryman, the 20-time Grand Slam winner Rafael Nadal, said he knew he had become a subject of fascination back home over the past few days.

“I’m trying not to think about this,” he said Sunday after beating Peter Gojowczyk of Germany in the fourth round, his second consecutive five-set win. “Just focus on New York, on every day here.”

That is a good start, said Mary Carillo, the tennis commentator and a former Grand Slam doubles champion. Carillo has seen tennis crack so many rising stars, from Andrea Jaeger, who tanked matches, to Mardy Fish, who battled anxiety and mental illness at the peak of his career. Her heart sinks every time she sees players checking their phones for what is being said about them on social media as soon as they walk off the court.

Survival, she said, comes down to the stuff we learn in kindergarten: Get enough sleep; don’t talk to strangers; don’t listen to what they say about you; stay away from bad people.

“You really better make sure you have the right people on your ball club,” Carillo said. “People who understand your values, your ambitions, how much you can take and most importantly when you need some time to step away.”