At Peoria High School he played Varsity baseball for four years and football for three, and was co-captain in both football and baseball his senior year. He was All-City guard his sophomore year, and All-City/Greater Peoria as a tackle his junior and senior years. During his senior year, he was named All-State by both the Chicago Daily News and Champaign News-Gazette. At Bradley University, Robertson started as Offensive Center in football for three years and Catcher/1st Baseman for three years (freshmen were ineligible at that time). He played Sunday Morning League baseball for twelve years.
In 1953, he began his coaching career at Princeville High School where he served as head basketball, assistant football and head track coach. Returning to Peoria High in 1956 as an assistant coach, he was head coach in football from 1957 to 1965, compiling a record of 50 wins, 20 losses and 8 ties. His 1963 team was undefeated and untied and his 1964 team was undefeated with a record of 9-0-1, the first in the history of the school, and the 1957 team was Big 12 Champion. In 1963 and 1964, his teams were Mid-State 9 Champions. He also coached wrestling, golf, and assisted in basketball, track and baseball.
Robertson left coaching for administration in 1965, serving through 1987. As principal of Peoria High School, he was instrumental in bringing the State Cross Country meet to Peoria, serving as meet manager for sixteen years. At Peoria High, he took the lead in developing many athletic programs and school facilities, including the Girls’ Athletic Program.
“Corky” introduced and administered the first experimental injury prevention condition program to the IHSA. He was a basketball official for 20 years on both the high school and college scene and worked many tournaments. He served the MidState Conference as its President several times, and he is the only individual to have played, coached and administered the annual Thanksgiving “Turkey Day” football game between Manual and Central.
He is the current president of The Greater Peoria Sports Hall of Fame and is enshrined there along with his father, “A.J.”, and brother “Jimmy”.