Sonny Grandelius was a versatile backfield threat for Muskegon Heights High School’s successive state champion teams in his junior and senior years of 1945 and 1946.  A quarterback in 1945, Grandelius switched to fullback in ’46 and was a first team All-State selection at that position.
Following graduation, he attended Michigan State University and further demonstrated his athletic versatility, earning a letter in boxing his sophomore year.  On the gridiron, he gained 184 yards in the 1950 season opener to establish a Spartan single game rushing mark.  Only the 17th player in the history of college football to rush for over 1,000 yards, Grandelius ended his senior season with another MSU record of 1,023 yards on the ground, and All-American honors. Selected by the New York Giants in the third round of the 1952 NFL draft, he played one season in the professional ranks before returning to Michigan State as an assistant coach under Hugh “Duffy” Daugherty.  In 1959, he accepted the head coaching position at the University of Colorado.
He joined the staff of the Philadelphia Eagles as a backfield coach in 1962, before moving to the Detroit Lions for the 1964 season in the same capacity.  In 1974, he was selected as the general manager of the Detroit Wheels of the World Football League.  Grandelius served as the chairman of the team selection committee for the Cherry Bowl, a college post-season football game hosted at the Pontiac Silverdome in 1984 and 1985.