That is the question on everyone's mind as they mourn the loss of Carlos Sanchez, a 16-year-old Moon Valley High School football player, who died suddenly after playing in a varsity football game.
Carlos died two days after taking a hit and collapsing during last game last Friday.
Initial fire department reports said Carlos suffered a seizure while on the field. Teammates said he took a hard hit and got up moments later.
However, an official cause of death won't be determined until the medical examiner releases autopsy results.
The Arizona Interscholastic Association, or AIA, which works closely with high schools to keep student athletes safe, said Moon Valley followed protocol.
"The information we were given is it was a typical football play that occurred. Tragedy happened in the course of the game." said Joe Paddock, the assistant executive director for the AIA.
"As far as AIA is concerned, there is nothing to investigate. It's definitely a school issue that they're covering. They're taking precautions," said Paddock.