Oklahoma linebacker Austin Box was found dead on Thursday. A close friend to Box told authorities that he thought Box had overdosed. Police are still investigating whether or not drugs had anything to do with the up and coming linebacker’s death. Austin Box was 22 years old.

According to reports, the Sooners linerbacker was discovered by John Cobble III, the son of Austin Box’s high school football coach Tom Cobble. Cobble expressed to an emergency dispatcher that Box had been taking pain pills and was not breathing. Upon arrival, police found Cobble administering CPR.

The Enid, OK native was expected to be the starting linebacker in the fall season for the Oklahoma Sooners. His team expressed heartfelt sorrow at the loss of their teammate, calling Austin Box a “great leader” and an “integral part in” the team’s success.

Brent Venables, Oklahoma defensive coordinator, said that the linebacker “exemplified everything you want in a player.” In a statement, Venables said of Box, “He stands for everything that’s right about this program.”

Austin Box’s family released a statement shortly after confirmation of his death stating, “Austin loved everything about Oklahoma — the people, his hometown of Enid and his many close friends. Most of all, Austin loved his family and we loved him. We invite you to join us in celebrating his life.”