A stellar receiver on teams of the late 1940’s, Dieckelman was the first winner of the O’Melia Award following the Holy Cross-Boston College game of 1945, and was a starter in the Orange Bowl Game vs. Miami in 1946. His best season was 1948 when he was selected All New England and All East, as well as honorable mention of several All American teams. He was also selected to play in the North-South Shrine game as a senior.
Dieckelman was drafted by the pros and signed with the New York Bulldogs. He was selected for the Eastern All Star Team as a rookie and was a starting offensive end.