A 15-year-old athlete died when a friend punched him in the chest during a classroom round of "cuss game" in which students hit each other for using profanity.

Russell Edwards died Tuesday of cardiac arrest, seconds after complimenting his 14-year-old buddy on a "good hit." The Oak Grove High School students engaged in the diversion while in science class.The 14-year-old friend, realizing what he had done, cried and prayed over Edwards' body while teachers tried in vain to revive the youth.

"The boy's totally devastated," detective Sgt. Walt Robinson said Wednesday. His grandmother told Robinson the boy can't sleep. "He keeps saying he's terribly sorry."

Edwards was a star athlete who played on the football, baseball and wrestling teams. A husky 5-foot-10, at 150 pounds he was just starting to grow into manhood.

The name of the 14-year-old who punched Edwards was not released. He was described as about 5-foot-10 and strong, but not as big as Edwards.

Police said no charges will be filed.

An autopsy was planned to verify the cause of death, but doctors said one blow to the chest could be fatal.

"If the blow is delivered with enough force at precisely the right moment in the cycle of the heart, that could cause the heart to stop beating," said Dr. Edward Perper, a cardiologist at Santa Clara Valley Medical Center.

The "cuss game" is popular among teenage boys. It starts with a "pinky shake." Then when a player uses profanity, the other hits him, usually in the upper body and often in the chest, until the victim says "cuss word" to stop the blows.

Police were uncertain what Edwards said before the fatal punch.

"Most of the kids are in a state of shock," said Oak Grove Principal Karalee Roland.

She said she was unaware of the game until now.