Xavier Jones stumbled, stopped and went down the day before Thanksgiving at La Verne Lutheran High School, about 40 miles east of downtown Los Angeles.
The senior's heart apparently had stopped and he wasn't breathing, but head coach Eric Cooper and assistant coach John Osorno administered cardiopulmonary resuscitation and were able to get him breathing again.
Cooper said that by chance, he had studied up on CPR the night before the incident, viewing instructions from an iPhone first-aid application called Phone Aid.
"It was really fresh and clear in my brain," Cooper told the Los Angeles Times. "We are trained in CPR, but the iPhone app was a stabilizer for us."
"He saved his life," the teen's father, David Jones, told the San Gabriel Valley Tribune.
Jones, who remained hospitalized, told the Times on Wednesday that he remembers nothing from the time he fell until he awoke from a medically induced coma 24 hours later.
"I'm just thankful and happy to be here," the Corona youth said. "Things could have been a lot worse."
Jones was diagnosed with hypertrophic cardiomyopathy, a sometimes-deadly thickening of the heart that impedes blood flow. Doctors are recommending he receive a defibrillator implant. The family is seeking a second opinion.
The disease killed Loyola Marymount basketball star Hank Gathers, who collapsed during a game in 1990.
Jones, who is 6-foot-8 and weighs 220 pounds, is the starting center on the La Verne team, which won a state championship last year.
His disease jeopardizes plans for the straight-A student to accept a basketball scholarship to West Point next year so he can study to be a doctor -- a dream Jones has had since he was 5.
"I'd ask him, 'Are you going to be an NBA player?' and he would say, 'No I'm going to be a doctor,"' Cooper said. "The decision was going to be based on his career, not just basketball."
Jones is worried about the future but told the Times he is undeterred.
"I'm just happy to be alive," he said.
(Copyright 2010 by The Associated Press. All Rights Reserved.)