But people close to Borrelli marvel at his maturity and positive attitude in the face of a rare disease that requires an unusual and potentially embarrassing treatment.
Borrelli has Mucha-Habermann disease, an autoimmune disease that manifests as a skin disorder. His father, Dave Borrelli, said the disease is so rare that when Josh was diagnosed as an eighth grader, he was the only person in the country believed to have it at the time.
"I told him with those odds, he ought to play the lottery," Dave Borrelli said.
The disease, which is not contagious, is a bit of a mystery, according to the National Organization of Rare Disorders website. There is no known cause. There is no known cure.
The disease is characterized by rashes and lesions that form on the skin, usually on the trunk and arms and legs. Borrelli takes medication, but his main treatment is eight minutes a day in a tanning bed, as ultraviolet therapy keeps the disease in check.
He can't miss a day, either.
"Sometimes, you get a little tired of it, going there all the time or going to the doctors all the time," Josh Borrelli said. "But I understand I have to do it. It's just a bump in the road."
Shawnee coach Joe Kessler marvels at more than Borrelli's skill set or willingness to make big shots for the Renegades in crucial moments - such as the two three-pointers that spurred a comeback from a five-point deficit in the fourth quarter Thursday.
Kessler said that Borrelli, who also is hearing-impaired, displays remarkable poise and perspective.
"He's going through what no high school student should have to go through," Kessler said. "It's unbelievable not only that he can perform the way he does but that he's so focused. But he's such a positive kid, such a great kid, he handles it so well."
Shawnee senior guard Ryan Bodnar, one of Borrelli's oldest friends, said his buddy never makes an issue of his condition.
"It's just something he deals with," Bodnar said. "We know what he's going through, but he doesn't let it bother him. It sure hasn't affected his play."
Borrelli first was diagnosed with the disease in the spring of his eighth-grade year. After about five months of medication and treatment, the disease went into remission for nearly four years.
It came back about a week before the start of practice for this senior season.
"The only time I heard him complain, he said, 'This timing is bad,'" Dave Borrelli said.
Josh Borrelli said he hopes the disease will fade again in a few months. He said doctors have told him he could deal with an outbreak every three or four years, although the disease is so rare that it's tough to establish a firm prognosis.
Borrelli made his father take him to the tanning salon for his first few visits so he could tell the workers that his son was there for medical treatment.
"I was kind of embarrassed that they would think I was a guy who wanted to get tan," Borrelli said.
For the most part, Borrelli deals with his disease with an upbeat approach and a self-deprecating sense of humor. That's why his buddies in the Shawnee student section are prepared to break out new T-shirts at the Renegades' next home game.
The words on front of the T-shirts read: "The J-Bo Show," in tribute to Borrelli's prowess on the court.
But the back has the poignant punch line: "Fear the Tan."
Contact Phil Anastasia at firstname.lastname@example.org or @PhilAnastasia on Twitter. Read his blog, "Jersey Side Sports," at www.philly.com/jerseysidesports