Rare two-page handwritten letter by football coaching legend Pop Warner, on his personal stationery. Warner was a key innovator of the modern game, credited with the single/double wing formations, three-point stance, and more. A 1951 College Football Hall of Fame inductee, he also helped launch Pop Warner youth football. The letter discusses invitations, the Pop Warner Foundation, and youth sports. Authenticated and encapsulated by PSA/DNA, a historic piece from one of football’s founding figures.